And the chondrichthyes are cartilaginous fish like sharks, rays and skates.
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Our preliminary hypothesis is that the creatures were green or blue, with long cartilaginous beaks.
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But he couldn't get off a safe shot to tag the shark on its cartilaginous fins.
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That's, of course, not what it is, as sharks are cartilaginous fish that lack bones, explained Houghton.
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Skates are "cartilaginous fish," along with sharks and rays, which means their gills are protected by skin flaps.
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Ear confit doesn't have a memorable taste, although its texture—a mix between crunchy and cartilaginous—is quite fun.
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Maybe the stir-fried duck tongues I ate last time could have slid from their cartilaginous framework more easily.
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In the following order, they researched: A. Sharks, skates and cartilaginous fish B. Bony fish C. Are dolphins fish?
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This study shows that this little bird would not have been ready to fly because the sternum (chest bones) were still cartilaginous.
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The pork-chop frisbees and cartilaginous ribs are unfortunate missteps, but the stewed beef and the oxtail are tender and tomato-rich.
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Some scientists think of it as the "missing link" between sharks and ray, two distinct kinds of cartilaginous fish that are actually closely related.
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Mr. Matibag keeps his own counsel and palate, preferring dinuguan without offal and sisig without the customary cartilaginous nubs of pig ear and snout.
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During the late Jurassic, around 150 million years ago, sharks (which are cartilaginous fish) and turtles were capable of slicing into flesh with their teeth.
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The secret of this acoustic diversity is a specialized avian vocal organ called the syrinx, which produces sounds with vibrating membrane folds attached to cartilaginous rings.
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They discovered that G. pacifica is especially warty, with cartilaginous bumps stretching down its arms and covering its mantle — the muscular covering for the octopus's organs.
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To celebrate the arrival of Shark Week and almost 30 years of these cartilaginous fish, we took a look back at Shark Week through the years.
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Mid-growth and covered in fuzz, the reindeers' cartilaginous antlers were then shipped to China, where they were ground up and sold as an aphrodisiac and health supplement.
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Of the hundreds of species of cartilaginous fish in the ocean, only two — the two known species of manta rays — exhibit this trait, and then only in some populations.
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"This work clearly shows tissue engineering approaches for reconstruction of the ear and other cartilaginous tissues will become a clinical reality very soon," he said of the new study.
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Because their juvenile cartilaginous frames would have been hard-pressed to bear weight on land, these Acanthostega tetrapods likely spent their younger years as an entirely aquatic species, they concluded.
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Scientists attached suction cup tags to to a cartilaginous part of the whale's back called the dorsal ridge, with a thread hooked to magnesium links — kind of like high-tech earrings.
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In the caustic brine, the cartilaginous feet and eggs would melt into a slurry of digestible calcium, minerals, and protein to be eaten beginning three days after the baby was born.
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In 18th century France, it was fairly common to come across objects made of Galuchat, a type of cartilaginous fish leather named after Jean-Claude Galluchat, the artisan who invented its tanning process.
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Qilinyu had three bones, the dentary, maxilla and premaxilla, that characterize the modern vertebrate jaw seen in bony fish, amphibians, reptiles, birds and mammals, though they are absent in the cartilaginous sharks and rays.
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Besides the plaster layer modeled over the bone, marine shells fill its sockets and soil fills its interior for support, transforming what would have been strict cartilaginous remains into an artful commemoration of the deceased.
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It is not an actual finger, but rather an evolutionary improvisation that builds on the wrist structure, with an augmented wrist bone accompanied by a cartilaginous extension, three muscles that move it and even a fingerprint.
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They followed a muscle that attaches to all primates' hands for mobility, but were surprised to find tiny tendons also connecting it to the palm and a nubby bone between the thumb and wrist with a cartilaginous extension.
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Within these 1,500 species, there are several different classes of fish that have the ability, such as certain types of sharks, which belong to a class of cartilaginous fishes — fish whose skeletons are made of cartilage, rather than bone.
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Out of the 1,85033 species of cartilaginous fish—sharks and their relatives, which include skates and rays – as many as one-quarter are estimated to be threatened with extinction, and the conservation status of nearly half is poorly known.
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Everyone knows that what they are about to eat is a mistake—it has a fucking toenail on it, for one thing, and it is just as cartilaginous and faintly mucoid as it looks, it tastes fetid and somehow damp.
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With his sous-chef, Luis Alamos, Mr. Lai layered fried blue catfish into sushi rolls, fanned slivers of raw lionfish on plates and slathered the moist flesh clinging to cartilaginous Asian carp ribs from Kentucky with a guava-based barbecue sauce.
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"We noticed when we followed the tendon up there that those bones had a cartilaginous extension," says North Carolina State University comparative anatomist Adam Hartstone-Rose, lead author on a new paper describing the work in the American Journal of Physical Anthropology.
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Chaney, on the other hand, followed Onto the Land with another ocean faring expedition, named Sharks, that focuses on the cartilaginous monsters of the deep, and is now hard at work on another foray into the world of wildlife documentary making in Los Santos.
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Despite a cannabis habit that would probably kill Snoop Dogg, the 253-year-old Floridian leads a fairly normal life: He's a senior stockbroker at a large securities firm, who spends every Saturday volunteering with disabled adults and children, while grappling with a rare bone disease called multiple congenital cartilaginous exotosis.
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A chondroma is a benign cartilaginous tumor, which is encapsulated with a lobular growing pattern. Tumor cells (chondrocytes, cartilaginous cells) resemble normal cells and produce the cartilaginous matrix (amorphous, basophilic material).
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The mantle of Cranchia scabra is covered in multi-pointed cartilaginous tubercles.Person, P. (1969). Cartilaginous dermal scales in cephalopods. Science 164(3886): 1404–1405.
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A synchondrosis (or primary cartilaginous joint) is a type of cartilaginous joint where hyaline cartilage completely joins together two bones. Synchondroses are different than symphyses (secondary cartilaginous joints) which are formed of fibrocartilage. Synchondroses are immovable joints and are thus referred to as synarthroses.
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Cartilaginous joints are connected entirely by cartilage (fibrocartilage or hyaline). Cartilaginous joints allow more movement between bones than a fibrous joint but less than the highly mobile synovial joint. Cartilaginous joints also forms the growth regions of immature long bones and the intervertebral discs of the spinal column.
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Cartilaginous fish, such as sharks, also lack a true maxilla. Their upper jaw is instead formed from a cartilaginous bar that is not homologous with the bone found in other vertebrates.
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The most distant homolog detectable is in cartilaginous fish (462.5 MYA).
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Chimaera is the type genus of the cartilaginous fish family Chimaeridae.
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The cartilage of Gogoselachus was very different from those of other cartilaginous fish and acanthodians. While the cartilage itself closely resembled modern shark cartilage, the matrix holding the cartilage cells together contained remnant bone cells. This means that in contrast to the previous idea that cartilaginous fish were jawed vertebrates that evolved before the advent of a bony skeleton, cartilaginous fish in fact evolved from bony ancestors. Cartilaginous fish most likely lost these bony skeletons in order to evade predators and catch prey faster.
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A regrown tail has a cartilaginous rod for support instead of vertebrae.
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Many common effects sharing similarity with chondrodysplasia punctata stem from cartilaginous origin. Radiography reveals extensive diffuse cartilaginous calcification. Pulmonary angiography and soft tissue radiography often demonstrate significant cartilaginous ossification in the trachea and larynx, with perichondral and endochondral centers significantly ossified in transformed cartilage. Abnormal diffuse cartilaginous ossification is typically most pronounced in the auricles and cartilage of the trachea and larynx, while peripheral pulmonary stenosis is frequently common in KS. In consanguineous parents of children with KS, one is often phenotypically normal, while the other is positive for pulmonary stenosis.
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There may also be an association with congenital cartilaginous rest of the neck.
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Parvalbumin has been identified as an allergen causing fish allergy (but not shellfish allergy). Bony fishes manifest β-parvalbumin and cartilaginous fishes such as sharks and rays manifest α-parvalbumin; allergenicity to bony fishes has a low cross- reactivity to cartilaginous fishes.
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Eostegostoma is an extinct genus of prehistoric cartilaginous fish from the Eocene epoch of Belgium.
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Cartilaginous fish (chondrichthyes) like sharks, rays and skates have a skeleton composed entirely of cartilage.
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Primary cartilaginous joints are known as "synchondrosis". These bones are connected by hyaline cartilage and sometimes occur between ossification centers. This cartilage may ossify with age. Some examples of primary cartilaginous joints in humans are the "growth plates" between ossification centers in long bones.
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A small cartilaginous nodule (cartilago triticea), sometimes bony, is frequently found in the lateral thyrohyoid ligament.
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Given time, the dislocated portion of the tail may be replaced by a stiff, cartilaginous rod.
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Radiation of cartilaginous fishes, including the Galeomorphi. Derived from work by Michael Benton, 2005.Benton, M. J. (2005) Vertebrate Palaeontology, Blackwell, 3rd edition, Fig 7.13 on page 185. Galeomorphii is a superorder of cartilaginous fishes which includes all modern sharks except the dogfish and its relatives.
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Zuni bluehead suckers eat algae and invertebrates off of rocks with the cartilaginous scraper in their mouths.
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Restorations of Menaspis and Deltoptychius Menaspis is an extinct genus of holocephalian cartilaginous fish from the Permian.
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Rhinopristiformes is an order of rays, cartilaginous fishes related to sharks, containing shovelnose rays and allied groups.
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Biconcave cartilaginous vertebrae are developed, and as is the case in most fishes, constrict the notochord vertebrally.
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Chondromyxoid fibroma is a type of cartilaginous tumor. Most cases are characterised by GRM1 gene fusion or promoter swapping. It can be associated with a translocation at t(1;5)(p13;p13). A chondromyxoid fibroma (CMF) is an extremely rare benign cartilaginous neoplasm which accounts for < 1% bone tumours.
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An easy way to distinguish the bluehead from the other Arizona suckers is the distinct cartilaginous lower jaw.
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There may be cartilaginous bodies attached to the synovium. Synovial involvement may be focal or diffuse in nature.
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The snails of this family can retract into their shell and close it off with a cartilaginous, flexible operculum.
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Chondrichthyes includes sharks, rays, skates, and sawfish. There are 48 species and six subpopulations of cartilaginous fish assessed as endangered.
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The bony (and cartilaginous) fish groups that emerged after the Devonian, were characterised by steady improvements in foraging and locomotion.
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As a cartilaginous fish, shark tissues usually do not fossilize. Squalus acanthias fossils date back to the Miocene 11 MYA.
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The common tunic is tough and cartilaginous, yellowish-brown and transparent. It is usually encrusted with sand and shell fragments.
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With keel. Cartilaginous. Like cartilage. Caudal. Tail-like, or with a tail-like appendage. Cellular. Made up of cells. Cerebral.
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Chondrichthyes includes sharks, rays, skates, and sawfish. There are 121 species and eight subpopulations of cartilaginous fish assessed as vulnerable.
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However, most of these characteristics are considered homologous characteristics derived from common placoderm ancestors, and present also in basal cartilaginous fish.
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Paraorthacodus is an extinct genus of cartilaginous fish. An unidentified species has been found in the Hasle Formation of Bornholm, Denmark.
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The tail is completely enclosed in the uropatagium (tail membrane), and the trailing edge of the uropatagium has calcars (cartilaginous spurs).
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Chondrichthyes includes sharks, rays, skates, and sawfish. There are 118 species and eight subpopulations of cartilaginous fish assessed as near threatened.
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Chondrichthyes includes sharks, rays, skates, and sawfish. There are 313 species and two subpopulations of cartilaginous fish assessed as least concern.
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Chondrichthyes includes sharks, rays, skates, and sawfish. There are 475 species and three subpopulations of cartilaginous fish evaluated as data deficient.
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He observes that the auditory organs of cetaceous, cartilaginous and spinose fish differ from one another in structure and substance. The auditory organs of cetaceous fish are bony, while they are more fragile for cartilaginous fishes, he explains. He adds that water does not act as an impediment to hearing, but rather is the “intermedium” by which sound is communicated.
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Radiation of cartilaginous fishes, derived from work by Michael Benton, 2005.Benton, M. J. (2005) Vertebrate Palaeontology, Blackwell, 3rd edition, Fig 7.13 on page 185. Cartilaginous fishes, class Chondrichthyes, consisting of sharks, rays and chimaeras, appeared by about 395 million years ago, in the middle Devonian, evolving from acanthodians. The class contains the sub classes Holocephali (chimaera) and Elasmobranchii (sharks and rays).
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Sialadenectomy specimen showing a well outlined solid neoplasm with cartilaginous areas. Morphological diversity is the most characteristic feature of this neoplasm. Histologically, it is highly variable in appearance, even within individual tumors. Classically it is biphasic and is characterized by an admixture of polygonal epithelial and spindle-shaped myoepithelial elements in a variable background stroma that may be mucoid, myxoid, cartilaginous or hyaline.
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The remaining cartilaginous portions of the epiphyses become thinner. As these cartilaginous zones become obliterated, the epiphyses are said to be "closed" and no further lengthening of the bones will occur. A small amount of spinal growth concludes an adolescent's growth. Pediatric endocrinologists frequently order bone age x-rays to evaluate children for advanced or delayed growth and physical development.
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Orodontidae is an extinct family of cartilaginous fish that lived from the late Pennsylvanian to the Early Permian in what is now North America.
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Cartilaginous fish included the angelshark Phorcynis and the ray Rhinobatus obtusatus. Invertebrates included rudists, bivalves, sea snails of the genus Nerinea, shrimp, and starfish.
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Turtles are reptiles of the order Testudines characterized by a special bony or cartilaginous shell developed from their ribs and acting as a shield.
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Sharks, and possibly other cartilaginous fishes, have immunoglobulin M (IgM) and immunoglobulin W (IgW) as well, both types with two heavy and two light chains.
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From the ninth cervical vertebra to the back, the vertebral joints show the remains of articular capsules. Between the spines at places very thin interspinal and supraspinal ligaments are visible. Six vertebrae are visibly capped by cartilaginous synchondroses, a typical juvenile feature. Cartilaginous caps are also present on all limb joints, even the smallest, and are especially thick in the shoulder, elbow and wrist joints.
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Batoidea is a superorder of cartilaginous fishes commonly known as rays. They and their close relatives, the sharks, comprise the subclass Elasmobranchii. Rays are the largest group of cartilaginous fishes, with well over 600 species in 26 families. Rays are distinguished by their flattened bodies, enlarged pectoral fins that are fused to the head, and gill slits that are placed on their ventral surfaces.
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Saddle nose is a condition associated with nasal trauma, congenital syphilis, relapsing polychondritis, granulomatosis with polyangiitis, cocaine abuse, and leprosy, among other conditions. The most common cause is nasal trauma. It is characterized by a loss of height of the nose, because of the collapse of the bridge. The depressed nasal dorsum may involve bony, cartilaginous or both bony and cartilaginous components of the nasal dorsum.
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Secondary cartilaginous joints are known as "symphysis". These include fibrocartilaginous and hyaline joints, which usually occur at the midline. Some examples of secondary cartilaginous joints in human anatomy would be the manubriosternal joint (between the manubrium and the sternum), intervertebral discs, and the pubic symphysis. Articulating bones at a symphysis are covered with hyaline cartilage and have a thick, fairly compressible pad of fibrocartilage between them.
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The trematodes or flukes include 18,000 to 24,000 species, divided into two subclasses. Nearly all trematodes are parasites of mollusks and vertebrates. The smaller Aspidogastrea, comprising about 100 species, are obligate parasites of mollusks and may also infect turtles and fish, including cartilaginous fish. The Digenea, the majority of trematodes, are obligate parasites of both mollusks and vertebrates, but rarely occur in cartilaginous fish.
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Sharks and rays typically have five pairs of gill slits that open directly to the outside of the body, though some more primitive sharks have six pairs and the Broadnose sevengill shark being the only cartilaginous fish exceeding this number. Adjacent slits are separated by a cartilaginous gill arch from which projects a cartilaginous gill ray. This gill ray is the support for the sheet- like interbranchial septum, which the individual lamellae of the gills lie on either side of. The base of the arch may also support gill rakers, projections into the pharyngeal cavity that help to prevent large pieces of debris from damaging the delicate gills.
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They are very similar in appearance and easily confused with Thyroptera tricolor which has a paler venter than dorsum, and two cartilaginous projections on the calcar.
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Adult males reach in body length with a long tail and weigh . The African palm civet's ear canal is not divided and cartilaginous at the end.
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In several ethnic groups, most significantly the Japanese, the tenth rib is sometimes a floating rib, as it lacks a cartilaginous connection to the seventh rib.
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The hairless involucre consists of hairless, cartilaginous bracts (or phyllaries) with papery, sometimes serrated edges. Those on the outside are oval, the inner phyllaries are narrower.
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The quadrate bone forms the lower jaw articulation in all classes except mammals. Evolutionarily, it is derived from the hindmost part of the primitive cartilaginous upper jaw.
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In cartilaginous fishes (e.g. sharks and rays) and agnathans (e.g. lampreys and hagfish), the chondrocranium persists throughout life.Kent, G.C & Miller, L. (1997): Comparative Anatomy of the Vertebrates.
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Ochopristis is a genus of Late Cretaceous cartilaginous fish whose fossils have been found in the Aguja and Pen Formations of Big Bend National Park, Texas, USA.
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Squatirhina is a genus of Late Cretaceous cartilaginous fish whose fossils have been found in the Aguja and Pen Formations of Big Bend National Park, Texas, USA.
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The human ear canal is divided into two parts. The elastic cartilage part forms the outer third of the canal; its anterior and lower wall are cartilaginous, whereas its superior and back wall are fibrous. The cartilage is the continuation of the cartilage framework of pinna. The cartilaginous portion of the ear canal contains small hairs and specialized sweat glands, called apocrine glands, which produce cerumen (ear wax).
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Cartilaginous fishes, such as sharks and rays, have one set of oral jaws made mainly of cartilage. They do not have pharyngeal jaws. Generally jaws are articulated and oppose vertically, comprising an upper jaw and a lower jaw and can bear numerous ordered teeth. Cartilaginous fishes grow multiple sets (polyphyodont) and replace teeth as they wear by moving new teeth laterally from the medial jaw surface in a conveyor-belt fashion.
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Cartilaginous fishes (sharks, rays and skates) have cartilaginous jaws. The jaw's surface (in comparison to the vertebrae and gill arches) needs extra strength due to its heavy exposure to physical stress. It has a layer of tiny hexagonal plates called "tesserae", which are crystal blocks of calcium salts arranged as a mosaic. This gives these areas much of the same strength found in the bony tissue found in other animals.
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Chondrostei is a group of primarily cartilaginous fish showing some degree of ossification. The cartilaginous condition is thought to be derived, and the ancestors of this group were bony fish with fully ossified skeletons. Members of this group share with the Elasmobranchii certain features such as the possession of spiracles, a heterocercal tail, and the absence of scales. Nevertheless, the fossil record suggests they have more in common with the teleosts.
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Each pharyngeal arch has a cartilaginous stick, a muscle component that differentiates from the cartilaginous tissue, an artery, and a cranial nerve. Each of these is surrounded by mesenchyme. Arches do not develop simultaneously but instead possess a "staggered" development. Pharyngeal pouches form on the endodermal side between the arches, and pharyngeal grooves (or clefts) form from the lateral ectodermal surface of the neck region to separate the arches.
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In cartilaginous fish there is also a shorter duct which drains the posterior (metanephric) parts of the kidney, and joins with the mesonephric duct at the bladder or cloaca. Indeed, in many cartilaginous fish, the anterior portion of the kidney may degenerate or cease to function altogether in the adult. Hagfish and lamprey kidneys are unusually simple. They consist of a row of nephrons, each emptying directly into the mesonephric duct.
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The acquired immune system, which has been best-studied in mammals, originated in jawed fish approximately 500 million years ago. Most of the molecules, cells, tissues, and associated mechanisms of this system of defense are found in cartilaginous fishes. Lymphocyte receptors, Ig and TCR, are found in all jawed vertebrates. The most ancient Ig class, IgM, is membrane-bound and then secreted upon stimulation of cartilaginous fish B cells.
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Prior to its discovery, symmoriids were thought to be related to sharks, in the group Elasmobranchii. However, CT scans of its relatively intact skull showed traits such as brain shape and inner ear structure that are shared with cartilaginous fish from the group Holocephali, which includes chimaeras. This implies that the first major radiation of cartilaginous fish after the Devonian extinction was in fact holocephalians, rather than sharks as commonly believed.
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Comparisons to modern shark species have shown that thelodont scales were functionally similar to those of modern cartilaginous fish, and likewise has allowed an extensive comparison between ecological niches.
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Crustospathula is a genus of five species of crustose lichens in the family Malmideaceae. They are characterized by their stalked and sometimes branched cartilaginous soredia and Bacidia-like apothecia.
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The lake sediments of the Lagerstätte provided fossil cartilaginous fishes and their egg capsules and unusual Triassic reptiles like Sharovipteryx and Longisquama.Fischer et al., 2011Unwin et al., 2003, pp.
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Canadian Association of Radiologists Journal. 2011 May; 62(2):151-153. The cause is unknown. In this condition, cartilaginous metaplasia takes place within the synovial membrane of the joint.
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In addition to having ordinary radioles, some Canalipalpata possess one or more highly modified radioles located on the dorsal part of the head. This specialized structure is called an operculum. The operculum is a cone- shaped cartilaginous structure located at the distal end of a long cartilaginous stalk. When threatened or disturbed, the animal withdraws rapidly into its protective calcareous tube and employs the operculum as a plug to occlude the entrance to the tube.
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The formation has a large cartilaginous fish assemblage, mainly belonging to the ground sharks, such as requiem sharks and hammerhead sharks; and, to a lesser extent, mackerel sharks, such as white sharks, sand sharks, and Otodontidae. Many shark teeth were associated with the extinct broad-tooth mako (Cosmopolitodus hastalis) and megalodon (Carcharocles megalodon). Other cartilaginous fish include eagle rays, sawfish, and angelsharks. Most of the bony fish findings represent tunas and croakers.
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Gogoselachus ("shark from the Gogo Formation") is an extinct genus of cartilaginous fish known from the late Devonian of Australia. It is one of the earliest well-preserved Devonian chondrichthyans (20 million years older than Cladoselache), as much more of the fish than just teeth and scales were preserved. This rare preservation reveals some unique discoveries about the evolution of the cartilage that was inside later cartilaginous fish such as sharks, rays, and chimaeras.
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Taken with the data, that mice lacking the pln gene cannot maintain stable cartilage, it is apparent that perlecan is essential to the maturation and stability of cartilaginous structure. This is supported by a study showing that knockdown of perlecan production inhibits the final stages of chondrogenic differentiation in C3H10T1/2 fibroblasts in culture. Bone development, i.e. mineralization of cartilaginous tissue, correlates with loss of perlecan and heparan sulfate at the chondro-osseous junction (COJ).
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The Australian ghostshark (Callorhinchus milii) is a cartilaginous fish (Chondrichthyes) belonging to the subclass Holocephali (chimaera). Sharks, rays and skates are the other members of the cartilaginous fish group and are grouped under the subclass Elasmobranchii. Alternative names include elephant shark, makorepe (in Māori), whitefish, plough-nose chimaera, or elephant fish. It is found off southern Australia, including Tasmania, and south of East Cape and Kaipara Harbour in New Zealand, at depths of .
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The gulf chimaera (Hydrolagus alberti) is a species of cartilaginous fish in the family Chimaeridae found near Mexico, the United States, and possibly Suriname. Its natural habitat is open seas.
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In the southern Indian city of Mangalore, a spicy dish called rakti, made of heavily spiced porcine offal and cartilaginous tissue, is considered a homely indulgence by the local Christian community.
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Vascular plants, particularly seeds, and the stems of some mushrooms, are sometimes called "cartilaginous", although they contain no cartilage.Eflora – Glossary. University of Sydney (2010-06-16). Retrieved on 2015-10-26.
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Guitarfishes and other cartilaginous fishes are preyed upon by the pigeye shark, particularly off South Africa. Though the pigeye shark will take prey from anywhere in the water column, it tends to hunt close to the sea floor. An apex predator, it feeds mainly on teleost fishes such as croakers, flatfishes, and cutlassfishes, and to a lesser extent on cartilaginous fishes, cephalopods, and decapod crustaceans. It has also been recorded eating gastropods, sea snakes, dolphins, and whale carrion.
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They are also produced in the Leydig's organ, which is only found in certain cartilaginous fishes. The subclass Holocephali, which is a very specialized group, lacks both the Leydig's and epigonal organs.
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Restoration of L. paludis The skeleton of Limnoscelis was relatively large, with Limnoscelis paludis measuring 7 feet (around 2 meters) long. Portions of the skeleton are poorly ossified, with many cartilaginous elements.
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Neoselachii are a grouping of cartilaginous fishes in subclass Elasmobranchii of class Chondrichthyes. It contains all living (extant) sharks, skates, and rays. The first known neoselachian is the Devonian (possible) hexanchiforme Mcmurdodus.
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Netsepoye is an extinct genus of cartilaginous fish distantly related to the modern order Chimaeriformes, containing the single species Netspoye hawesi. It lived more than 320 million years ago during the Late Mississippian.
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Extreme downgrowth of the pterygoid processes of the basisphenoid. Lightly built postorbitofrontal processes. The pineal foramen is located in the centre of the triangular parietal table. The supraoccipital loose cartilaginous contact with parietal.
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The roundel skate or Texas clearnose skate (Rostroraja texana) is a species of cartilaginous fish in the family Rajidae. It is found in the Gulf of Mexico, Southeast Florida and the Yucatan Peninsula.
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It consists of two interlocking components: one located on the mantle (often fibrous) and the other on the funnel (often cartilaginous). The apparatus may permit some anterior–posterior displacement or prevent movement altogether.
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MMP-1 (interstitial collagenase) cleaves collagen type I, II, III, VII and X. Therefore, tenascin C over-expression can significantly alter collagen in the ECM and influence tumor cell migration in cartilaginous tissues.
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Humpback whale fluke They have a cartilaginous fluke at the end of their tails that is used for propulsion. The fluke is set horizontally on the body, unlike fish, which have vertical tails.
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Acrodus is an extinct genus of cartilaginous fish from the Permian to Paleocene periods.Johnson, G., 1981. Hybondontoidei (Chondrichthyes) from the Witchita- Albany Group (Early Permian) of Texas. Journal of Vertebrate Paleontology. 1:1.
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Chondrichthyes (; from Greek χονδρ- 'cartilage', ἰχθύς 'fish') is a class that contains the cartilaginous fishes: they are jawed vertebrates with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage rather than bone. The class is divided into two subclasses: Elasmobranchii (sharks, rays, skates, and sawfish) and Holocephali (chimaeras, sometimes called ghost sharks, which are sometimes separated into their own class). Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates.
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Early Eocene fossil stingray Heliobatis radians Batoids belong to the ancient lineage of cartilaginous fishes. Fossil denticles (tooth-like scales in the skin) resembling those of today's chondrichthyans date at least as far back as the Ordovician, with the oldest unambiguous fossils of cartilaginous fish dating from the middle Devonian. A clade within this diverse family, the Neoselachii, emerged by the Triassic, with the best-understood neoselachian fossils dating from the Jurassic. The oldest confirmed ray is Antiquaobatis, from the Pliensbachian of Germany.
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Early Eocene fossil stingray Heliobatis radians Skates belong to the ancient lineage of cartilaginous fishes. Fossil denticles (tooth-like scales in the skin) resembling that of today's chondrichthyans date at least as far back as the Ordovician, with the oldest unambiguous fossils of cartilaginous fish dating from the middle Devonian. A clade within this diverse family, the Neoselachii, emerged by the Triassic, with the best-understood neoselachian fossils dating from the Jurassic. This clade is represented today by sharks, sawfish, rays and skates.
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In females, the voice is three tones lower than the child's and has five to twelve formants, as opposed to the pediatric voice with three to six. The length of the vocal fold at birth is approximately six to eight millimeters and grows to its adult length of eight to sixteen millimeters by adolescence. The infant vocal fold is half membranous or anterior glottis, and half cartilaginous or posterior glottis. The adult fold is approximately three-fifths membranous and two-fifths cartilaginous.
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In January 2014, Nature reported research into the Australian ghostshark genomeAuthor: Byrappa Venkatesh, a comparative-genomics expert at the Agency for Science, Technology and Research, Singapore that showed they lack a single gene family that regulates the process of turning cartilage into bone, and indicates a gene duplication event gave rise to the transformation in bony vertebrates.Why sharks have no bones: (Callorhinchus milii) Elephant shark's genome - the first of a cartilaginous fish - exposes early evolution of vertebrates., Brendan Borrell, Nature, 8 January 2014, accessed 9 January 2014 The Australian ghostshark was proposed as a model cartilaginous fish genome because of its relatively small genome size. Its genome is estimated to be 910 megabases long, which is the smallest among all the cartilaginous fishes and one-third the size of the human genome (3000 Mb).
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C21orf58 orthologs were identified in bony fish but not in cartilaginous fish. The first 35 bases of DUF4587, Arg234\- Pro265, were conserved across ortholog sequences. The most distantly related ortholog identified was the zebrafish.
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Both the upper and lower teeth are plate-shaped (9). Of note, the spotted ratfish does not have a cartilaginous appendage to the frontonasal region (2), which is a common feature of the chimera.
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Phorcynis is an extinct genus of cartilaginous fish. the scales of Phorcynis have elongated crowns with a narrow median keel and short lateral folds and the teeth are asymmetrical, similar to those of Orectolobus.
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The neurocranium arises from paraxial mesoderm. There is also some contribution of ectomesenchyme. In Chondrichthyes and other cartilaginous vertebrates this portion of the cranium does not ossify; it is not replaced via endochondral ossification.
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Instead of an external calcareous shell, they possess a pseudoconch, consisting of conchioline, a cartilaginous tissue. The mantle and the gill have disappeared as well. They breathe through the skin. They prefer warm water.
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Harriotta is a genus of cartilaginous fish in the family Rhinochimaeridae. Some common names for species in the genus include bentnose rabbitfish, bigspine spookfish, longnose chimaera, long-nosed chimaera, longnosed chimaera, and narrownose chimaera.
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Its habitat was apparently shallow or epicontinental seas, as evidenced by its associated fauna, the cartilaginous fish Pseudocorax, Scapanorhynchus texanus and Serratolamna serrata, and the molluscs Cymprimera, Ethmocardium, Eutrephoceras, Platyceramus vanuxemi, Sphenodiscus and Turritella vertibroides.
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Plethodids possessed thin, angelfish-like bodies and often had high dorsal fins which made them distinctive from other types of fish. Their skeletons were partially cartilaginous, though the amount varied from one species to another.
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Pygmy skates are cartilaginous fish belonging to the family Gurgesiellidae in the superorder Batoidea of rays. Nineteen species in three genera are known.Weigmann, S., Séret, B., Last, P.R. & McEachran, J.D. 2016. Pygmy Skates, Family Gurgesiellidae.
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'Fancy' Goldfish (Carassius Auratus) swimming A reported 33,400 species of fish, including bony and cartilaginous fish, had been described by 2016, more than all other vertebrates combined. About 60% of fish species live in saltwater.
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However, some have argued that the remains of E. kawai are actually those of another prehistoric cartilaginous fish, Ischyodus, which lived about the same time and has also been compared to the rabbitfish Chimaera monstrosa.
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SBK3 diverged from cartilaginous fishes around 400 years ago, birds and reptiles around 300 million years ago, non-primate mammals around 90 million years ago. Divergence from primates last occurred around nine million years ago.
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The protein parvalbumin has been identified as the major allergen causing fish allergy (but not shellfish allergy, which is caused by tropomyosin). Parvalbumin is resistant to heat and enzymatic digestion, so cooking does not diminish its allergenic potency, nor do digestive enzymes. Bony fishes manifest β-parvalbumin whereas cartilaginous fishes such as sharks and rays manifest α-parvalbumin; allergenicity to bony fishes has a low cross-reactivity to cartilaginous fishes. In addition to β-parvalbumin, fish enolase, aldolase and collagen can also trigger allergic reactions.
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Near the nasal part of the interior surface of the frontal bone is a depression, the trochlear fovea, or occasionally a small trochlear spine, for the attachment of the cartilaginous pulley of the Obliquus oculi superior.
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There are two opposing views on the nature of chondroblastoma, one favoring an osseous origin and the other favoring a cartilaginous origin. The work of Aigner et al suggests that chondroblastoma should be reclassified as a bone-forming neoplasm versus a cartilaginous neoplasm due to the presence of osteoid matrix, type I collagen, and absence of true cartilage matrix (collagen II). However, Edel et al found that collagen II, a marker for mature chondrocytes, was expressed in chondroblastoma, supporting the chondroid nature of the neoplasm. The results of Romeo and colleagues favor the view of Edel et al of chondroblastoma being cartilaginous in nature but recognize that any definitive determinations regarding the origin of this neoplasm are not possible because of the plasticity of mesenchymal cells when set into different microenvironments and static approaches used in literature.
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The centers for the arch appear about the seventh or eighth week of fetal life, while the centers for the body appear in about the fourth or fifth month. The dens, or odontoid process, consists originally of a continuation upward of the cartilaginous mass, in which the lower part of the body is formed. About the sixth month of fetal life, two centers make their appearance in the base of this process: they are placed laterally, and join before birth to form a conical bilobed mass deeply cleft above; the interval between the sides of the cleft and the summit of the process is formed by a wedge-shaped piece of cartilage. The base of the process is separated from the body by a cartilaginous disk, which gradually becomes ossified at its circumference, but remains cartilaginous in its center until advanced age.
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Polyides rotunda grows to in length, its cartilaginous, terete and branches two or three times dichotomously. The branches are about in diameter reaching a uniform height. The holdfast is disc like. In colour it is purplish red.
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It could not be found in the bony fish order lophiiformes. TMEM151B is present in cartilaginous fishes, specifically sharks. TMEM151B was not found for lampreys or rays in BLAST; however, TMEM151B was found in BLAT for lampreys.
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Its ears are long, while the tragi, or cartilaginous flaps that project in front of the ear openings, are long. The tragi are blunt at the tips and considered of medium length for a mouse-eared bat.
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These fish include both bony fish and cartilaginous fish, the latter group represented by sharks and rays of various types. Marine reptiles are uncommon in this formation, and, besides Acamptonectes are represented by some fragmentary plesiosaur remains.
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Placoid scales on a lemon shark (Negaprion brevirostris) Placoid scales are found on cartilaginous fish including sharks. These scales, also called denticles, are similar in structure to teeth, and have one median spine and two lateral spines.
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In a study of early jawed vertebrate relationships, Davis et al. (2012) found acanthodians to be split among the two major clades Osteichthyes (bony fish) and Chondrichthyes (cartilaginous fish). The well- known acanthodian Acanthodes was placed within Osteichthyes, despite the presence of many chondrichthyan characteristics in its braincase. However, a newly described Silurian placoderm, Entelognathus, which has jaw anatomy shared with bony fish and tetrapods, has led to revisions of this phylogeny: acanthodians were then considered to be a paraphyletic assemblage leading to cartilaginous fish, while bony fish evolved from placoderm ancestors.
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Cartilaginous fishes, like this shark, have fins that are elongated and supported with soft and unsegmented rays named ceratotrichia, filaments of elastic protein resembling the horny keratin in hair and feathers Caudal fin of a grey reef shark Cartilaginous fishes form a class of fishes called Chondrichthyes. They have skeletons made of cartilage rather than bone. The class includes sharks, rays and chimaeras. Shark fin skeletons are elongated and supported with soft and unsegmented rays named ceratotrichia, filaments of elastic protein resembling the horny keratin in hair and feathers.
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Male cartilaginous fishes (sharks and rays), as well as the males of some live-bearing ray finned fishes, have fins that have been modified to function as intromittent organs, reproductive appendages which allow internal fertilization. In ray finned fish they are called gonopodia or andropodia, and in cartilaginous fish they are called claspers. Gonopodia are found on the males of some species in the Anablepidae and Poeciliidae families. They are anal fins that have been modified to function as movable intromittent organs and are used to impregnate females with milt during mating.
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Sturgeon are comparatively basal species of fish, whose earliest fossils date back to the Cretaceous period. They are best-known members of the bony fish taxon Chondrostei, a group of bony fishes that have cartilaginous skeletons superficially similar to the skeletons seen in the unrelated chondrichthyan fishes. In Qing dynasty Chinese cuisine, its meat and cartilaginous skeleton was often cooked and served together, and considered a delicacy. Adult Chinese sturgeon can range between in total length, and weigh between , ranking them among the largest sturgeon in the world.
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The cleithrum bone, forming the posterior margin of the gill chamber, also functioned as anchoring for the pectoral fins. The cartilaginous fishes do not have such an anchoring for the pectoral fins. This allowed for a movable joint at the base of the fins in the early bony fishes, and would later function in a weight bearing structure in tetrapods. As part of the overall armour of rhomboid cosmin scales, the skull had a full cover of dermal bone, constituting a skull roof over the otherwise shark-like cartilaginous inner cranium.
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Keutel syndrome is an autosomal recessive disorder caused by a novel loss-of-function mutation in the matrix Gla protein gene (MGP). MGP protein resides in the extracellular matrix and is implicated in inhibiting calcification though the repression of bone morphogenetic protein 2 (BMP2). Mutations resulting in loss of consensus donor splice site at exon 2-intron 2 junctions result in significant diffuse calcification of soft tissue cartilage. Extensive diffuse cartilaginous calcification is present in MGP-knockout mice, manifesting in vascular media replacement with a cartilaginous, chondrocyte-like matrix, and ultimately premature death.
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The remains of Gogoselachus were first discovered in 2005 by John A. Long in the Gogo Formation of Kimberly, making it the first known cartilaginous fish from the Gogo formation in over 60 years. The specimen was found inside a broken concretion, and was made up of the complete lower jaws, the shoulder blades, gill-arches, scales and teeth. During the specimen's preparation (dissolving the surrounding limestone with acetic acid), the cartilaginous elements were released surprisingly quickly, meaning that the fish's skeleton was made up of a special kind of mineralized cartilage.
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Chimaeras differ from other cartilagenous fish, having lost both the spiracle and the fifth gill slit. The remaining slits are covered by an operculum, developed from the septum of the gill arch in front of the first gill. The shared trait of breathing via gills in bony fish and cartilaginous fish is a famous example of symplesiomorphy. Bony fish are more closely related to terrestrial vertebrates, which evolved out of a clade of bony fishes that breathe through their skin or lungs, than they are to the sharks, rays, and the other cartilaginous fish.
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The simpler structure is found in jawless fish, in which the cranium is normally represented by a trough-like basket of cartilaginous elements only partially enclosing the brain, and associated with the capsules for the inner ears and the single nostril. Distinctively, these fish have no jaws. Cartilaginous fish, such as sharks and rays, have also simple, and presumably primitive, skull structures. The cranium is a single structure forming a case around the brain, enclosing the lower surface and the sides, but always at least partially open at the top as a large fontanelle.
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Placoid scales as viewed through an electron microscope. Also called dermal denticles, these are structurally homologous with vertebrate teeth. Placoid (pointed, tooth-shaped) scales are found in the cartilaginous fishes: sharks, rays. They are also called dermal denticles.
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Gloeoporus fungi have pore surfaces featuring a pinkish white, cream, or orange to deep reddish colour. The pores are small. The texture of the fruit bodies surface is gelatinous when fresh, but becomes resinous and cartilaginous when dry.
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Herbivores grind their molars together as they chew (masticate), and the ridges help to shred tough plant material. A material similar to dentin forms the hard material that makes up dermal denticles in sharks and other cartilaginous fish.
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Early work on lubricin showed that it was able to lubricate non cartilaginous surfaces as effectively as whole synovial fluid, confirming its important biological lubrication role. Understanding lubricin is key to understanding joint mechanics and friction-based diseases.
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1 Valparaíso Mar. 2012 Despite its name, it does not belong to the clade Selachii used for the modern classification of sharks. It is, however, distantly related to the sharks in the sense that both are Chondrichthyes (cartilaginous fishes).
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M. japonicus lives in bays and inland seas, particularly where warm currents occur. It is nocturnal, remaining buried in the substrate during the day. Its predators include bony fishes and cartilaginous fishes. When the sea temperature exceeds , spawning can begin.
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Rhomaleodus is an extinct genus of basal selachimorph elasmobranchii cartilaginous fish known from the Middle Triassic (Anisian stage) of Bulgaria. It was first named by Plamen S. Andreev and Gilles Cuny in 2012 and the type species is Rhomaleodus budurovi.
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The Yantai stingray was described by Yuanting Chu in his 1960 Cartilaginous Fishes of China, based on specimens obtained from the Shanghai Fish Market, Dongfushan, and Huaniao.Catalog of Fishes (Online Version). California Academy of Sciences. Retrieved on January 8, 2010.
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It consists of thin mineralized circular plates growing from the back end of the middle rib shaft and overlapping the front edge of the subsequent rib. Such plates are better known from Talenkauen and Thescelosaurus, and were probably cartilaginous in origin.
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Hybodontiformes are identified in the fossil record predominantly based on distinct teeth and fin spines. They were known to live in both fresh and salt water environments. Radiation of cartilaginous fishes, including the Hybodontiformes. Derived from work by Michael Benton, 2005.
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Sandalodus is an extinct genus of cartilaginous fish from the Carboniferous period.Fossils (Smithsonian Handbooks) by David Ward (Page 207) It was named by Newberry and Worthen in 1866. Eastman 1903 gave Cochliodontidae as the parent taxon while Sepkoski 2002 suggested Holocephali.
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Spotted oceanic triggerfish display plasticity in their eating habits, being considered either a carnivorous or a planktivorous fish. Upon examination, they consume smaller fish, Halobates (sea skaters), members of the order “Siphonophores,” and smaller cartilaginous fish (Senta et al., 1993).
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Asterolepis lower jaw Reconstruction of Asterolepis dermal skeleton Sketches of Asterolepis fossil found in 1889 by Woodward Fossil of Asterolepis maxima Primitive features such as jaw ossifications, a palatoquadrate, and a Meckel's cartilage are present in the Asterolepis that are important features shared between antiarchs and other Gnathostomata. Additionally the Asterolepis has box-like dermal armour covering the head and thorax with highly modified pectoral fins that are enclosed in interlocking dermal plates protecting a cartilaginous endocranium and gill region. Also, the vertebral column and the pectoral girdle are cartilaginous. The Asterolepis does not have an anal fin or pelvic fins.
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Southern African pilchard are the most important prey species of copper sharks off South Africa. The copper shark feeds more towards the bottom of the water column than the top, consuming cephalopods, including squid (Loligo spp.), cuttlefishes, and octopus; bony fishes, including gurnards, flatfishes, hakes, catfishes, jacks, Australian salmon, mullets, sea breams, smelts, tunas, sardines, and anchovies; and cartilaginous fishes, including dogfish sharks (Squalus spp.), stingrays, skates, electric rays, and sawfishes. Cephalopods and cartilaginous fishes become relatively more important food for sharks over long. Young sharks also consume scyphozoan jellyfish and crustaceans, including mud shrimps (Callianassa) and penaeid prawns.
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In cartilaginous fish, the zonular fibres are replaced by a membrane, including a small muscle at the underside of the lens. This muscle pulls the lens forward from its relaxed position when focusing on nearby objects. In teleosts, by contrast, a muscle projects from a vascular structure in the floor of the eye, called the falciform process, and serves to pull the lens backwards from the relaxed position to focus on distant objects. While amphibians move the lens forward, as do cartilaginous fish, the muscles involved are not homologous with those of either type of fish.
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In the northwestern Atlantic, around 60% of the dusky shark's diet consists of bony fishes, from over ten families with bluefish (Pomatomus saltatrix) and summer flounder (Paralichthys dentatus) being especially important. Cartilaginous fishes, mainly skates and their egg cases, are the second-most important dietary component, while the lady crab (Ovalipes ocellatus) is also a relatively significant food source. In South African and Australian waters, bony fishes are again the most important prey type. Newborn and juvenile sharks subsist mainly on small pelagic prey such as sardines and squid; older sharks over long broaden their diets to include larger bony and cartilaginous fishes.
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Prophylactic treatment of canine osteoarthritis with glycosaminoglycan polysulfuric acid ester. Arth Rheum 1989;32:759-766. However, mixed results have been reported on its ability to actually repair cartilaginous defects present at time of injection.McIlwraith CW, Frisbie DD, Kawcak CE. Polysulfated Glycosaminoglycan. Proc.
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An intermediate power of a microscopic view of an accessory auricle. The lesions presents as a nodule or papule, either sessile or pedunculated. They may be soft or have a cartilaginous structure. By histologic examination, it is a recapitulation of normal external auricle.
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Orodus is an extinct genus of cartilaginous fish that lived from the late Pennsylvanian to the early Permian in what is now North America. Growing up to 2 m (7 ft) in length, it was quite large for sharks of its time.
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The stipe has a white to ocher, equal, tough, and cartilaginous structure with fibrillose patches. It is 4 to 10 cm long and around .25 cm thick. The partial veil is thin, cortinate, and does not usually leave any remnants on the stipe.
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If the trachea is also involved the term tracheobronchomalacia (TBM) is used. If only the upper airway the trachea is involved it is called tracheomalacia (TM). There are two types of bronchomalacia. Primary bronchomalacia is due to a deficiency in the cartilaginous rings.
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587 Pp. Smithsonian Institution Press, , Birds and reptiles have bony uncinate processes on their ribs that project caudally from the vertical section of each rib. These serve to attach sacral muscles and also aid in allowing greater inspiration. Crocodiles have cartilaginous uncinate processes.
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Cladoselachidae is an extinct family of cartilaginous fishes and among the earliest predecessors of modern sharks. They are the only members of the order Cladoselachiformes and were characterized by having an elongated body with a spine in each of the two dorsal fins.
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Chondracanthus is a red algae genus in the family Gigartinaceae. The name Chondracanthus is from } (' or chondrus) meaning 'cartilage' and (') meaning 'spine or thorn,' together meaning 'with cartilaginous spines.' This refers to the rubbery papillae on the surface of the blades containing the reproductive structures.
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Bandringa rayi fossil shark, Mazon Creek Lagerstatte. This is the holotype specimen of the species. Its size and lack of developed cartilaginous skeletal structures indicate that this is a juvenile shark. The Mazon Creek fauna has over 320 species of animals that have been identified.
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The costochondral joints are the joints between the ribs and costal cartilage in the front of the rib cage. They are hyaline cartilaginous joints (i.e. synchondrosis or primary cartilagenous joint). Each rib has a depression shaped like a cup that the costal cartilage articulates with.
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The snout slightly projects beyond the mouth, often studded with pores. A pair of small maxillary barbells is hidden inside the labial fold. There is no cartilaginous support to the lips. The dorsal originates midway between the snout tip and the anterior base of anal.
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This list of fossil fishes described in 2013 is a list of new taxa of placoderms, fossil cartilaginous fishes and bony fishess of every kind that have been described during the year 2013. The list only includes taxa at the level of genus or species.
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The following is the full list of the extant species in Class Chondrichthyes, or the cartilaginous fish. Members of this class have a backbone, gills, no swim bladder, jaws, and a skeleton made of cartilage, a soft, strong material as a replacement for bone.
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The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 161–177. . The skull in fishes is formed from a series of only loosely connected bones. Jawless fish and sharks only poses a cartilaginous endocranium, with both the upper and lower jaws being separate elements.
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Second Edition. Wild Nature Press, Plymouth, UK narrow and grow up to thirty centimetres long. They do not include airbladders as in some other species of Fucus. The fronds are fairly rigid and cartilaginous, partially flattened, and olive green to yellowish green in colour.
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Bony fishes typically have fin rays rather than a fleshy makeup that you see in cartilaginous fishes. Often, you will also see a swim bladder within bony fishes which acts as a floatation tool, allowing the fish to adjust its depth in the water.
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Young Raja undulata at the Aquarium of Genoa There are few data about biology of this species. Using vertebrae as growth markers, maximum lifespan was supposed to be 21–23 years. It's an oviparous cartilaginous fish. The females lay their eggs from March to September.
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Fucheng, Zhang, Zhou Zhoghe, Hou Lianhai & Gu Gang 2001. Early diversification of birds: Evidence from a new opposite bird. Chinese Science Bulletin. 46(11):945-949 PDF Although among living vertebrates, bony uncinate processes are unique to birds, cartilaginous uncinate processes are present in crocodiles.
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Leaves frequently show an intercalary meristem and are usually fringed with cartilaginous teeth. The leaf apices are also often truncate (cut off). The flowers may be actinomorphic to zygomorphic, with a perigone tube with free stamens. The fruit is indehiscent, irregular, and often rostellate (rosetted).
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Cartilaginous bodies or osteocartilaginous bodies with central ossification may be noted. They are typically spherical in shape. Sizes range from several millimeters to several centimeters in diameter. The synovium of the involved joint demonstrates villous hyperplasia, which imparts a wrinkled appearance on gross examination.
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Prieto-Márquez and Wagner further suggested that sedimentary ridges within the depression likely represent former soft-tissue structures. The rear edge of the bony nostril was extended towards the front by a flange which was probably a cartilaginous structure, indicating that the rear part of the bony nostril was covered by soft tissue, forming a nasal cavity. As this covering was apparently restricted to the rear part, it is likely that the opening of the nasal passage into the skull interior would also have been situated there. A ridge running diagonally across the depression might have been a cartilaginous septum supporting a nasal cavity.
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A similar arrangement was found in primitive tetrapods, but in the evolutionary line that led to reptiles, mammals and birds, the intercentrum became partially or wholly replaced by an enlarged pleurocentrum, which in turn became the bony vertebral body. In most ray-finned fishes, including all teleosts, these two structures are fused with and embedded within a solid piece of bone superficially resembling the vertebral body of mammals. In living amphibians, there is simply a cylindrical piece of bone below the vertebral arch, with no trace of the separate elements present in the early tetrapods. In cartilaginous fish such as sharks, the vertebrae consist of two cartilaginous tubes.
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It included paraglossalia at the sides, paired first and second ceratobranchials and higher epibranchials. Also the bone structure suggested that in the middle a cartilaginous basihyal was present. The strong development of the hyoid would indicate that a powerful tongue compensated for the weakly developed dentition.
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The mantle of Cranchia scabra is covered in numerous multi-pointed cartilaginous tubercles Ventral view of an adult Galiteuthis glacialis from the Ross Sea, with a mantle length of 32.1 cm Different cephalopod dermal structures are hypothesised to play roles in buoyancy, locomotion, and even pseudoskeletal support.
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Metopacanthus is an extinct genus of cartilaginous fish from the Early Jurassic epoch in Europe. It is known from the Toarcian of the Posidonia Shale of Germany. It is unusual due to being an extrange aberrant Chimaera, with a jaw-like structure over the skull.E. Fraas. 1910.
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In Pursuit of Early Mammals by Zofia Kielan-Jaworowska His name is lent to the eponymous "Reichert's cartilage", described as a cartilaginous structure in the second branchial arch from which develop the temporal styloid processes, the stylohyoid ligaments, and the lesser cornu of the hyoid bone.
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The fins are carried by the thoracic vertebrae, ranging from nine to seventeen individual vertebrae. The sternum is cartilaginous. The last two to three pairs of ribs are not connected and hang freely in the body wall. The stable lumbar and tail include the other vertebrae.
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In the newborn, the symphysis pubis is 9–10 mm in width, with thick cartilaginous end-plates. By mid-adolescence the adult size is achieved. During adulthood the end-plates decrease in width to a thinner layer. Degeneration of the symphysis pubis accompanies aging and postpartum.
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CT is best utilized in earlier stages of the disease process, before cartilaginous bodies have calcified (become filled with calcium). CT can effectively detect non-calcified masses or those with only minimal calcification, which allows the radiologist to distinguish this condition from a simple joint effusion.
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It is hairy brown when new, turning yellow-orange, and has cartilaginous flesh that dries woody. It contains a black seed with a red aril which resembles that of nutmeg.Pycnanthus angolensis. PROTA. The fruit ripens over a long period continuing into the next flowering season, which begins around October.
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Fenestraja plutonia is a species of cartilaginous fish in the family Gurgesiellidae. It is commonly known as the underworld windowskate or Pluto skate. The underworld windowskate is known from patches of continental slope in the western Atlantic Ocean between the coasts of the southern United States and Suriname.
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This plate extends to form the chief part of the bone, the scapular spine growing up from its dorsal surface about the third month. Ossification starts as membranous ossification before birth. After birth, the cartilaginous components would undergo endochondral ossification. The larger part of the scapula undergoes membranous ossification.
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L. galeatus feeds primarily on macroalgae, and occasionally on detritus. The giant conch is preyed upon by invertebrates, such as octopuses, and also by vertebrates, including rays (genera and species of cartilaginous fish in the family Myliobatidae), triggerfish (family Balistidae), and snappers (perciform fish in the family Lutjanidae).
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They are covered in slime when taken from the water. The skeleton of the lungfish is partly bone, and partly cartilage. The vertebrae are pure cartilage, while the ribs are hollow tubes filled with a cartilaginous substance. The body of the lungfish is covered with large, bony scales.
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Iniopteryx ("Nape Wing") is an extinct genus of cartilaginous fish. It is from the Pennsylvanian epoch of the Carboniferous period, approximately 300 million years ago. Their fossils have been found in North America, primarily in two states: Ohio and Montana. In general, very little is known about this species.
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Some individuals can also have a small mark of the same color on the top of their heads. The red-eared slider does not have a visible outer ear or an external auditory canal; instead, it relies on a middle ear entirely covered by a cartilaginous tympanic disc.
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Limnoscelis had single headed ribs,, though they might have had cartilaginous caps to allow the passage of the vertebral artery between the capitulum and tubercle of each rib. Limnoscelis had two sacral vertebrae, a feature shared with amniotes, though the second sacral vertebra is reduced compared to the first.
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Dipturus teevani, commonly known as the prickly brown ray or Caribbean skate, is a species of cartilaginous fish in the family Rajidae. The prickly brown ray is medium in size compared to other skates, and is known from a patchy, deep-water distribution in the western Atlantic Ocean.
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For species in some genera (for example, Vampyrum and Phyllostomus), the calcar is entirely made of cartilage. In other genera (e.g. Saccopteryx, Pteronotus, Molossus), the calcar is calcified. Intermediate between these two forms is when one end of the calcar is calcified, while the other is cartilaginous (e.g.
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Upper respiratory system, showing entrance to auditory tube near middle. The Eustachian tube extends from the anterior wall of the middle ear to the lateral wall of the nasopharynx, approximately at the level of the inferior nasal concha. It consists of a bony part and a cartilaginous part.
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Bony fish have three pairs of arches, cartilaginous fish have five to seven pairs, and primitive jawless fish have seven. The vertebrate ancestor no doubt had more arches, as some of their chordate relatives have more than 50 pairs of gills.Romer, A.S. (1949): The Vertebrate Body. W.B. Saunders, Philadelphia.
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Metaplastic synovium organizes into nodules. With minor trauma, nodules are shed as small bodies into the joint space. In some patients, the disease process may involve tendon sheaths and bursal sacs. Cartilaginous intra-articular bodies float freely within the synovial fluid, which they require for nutrition and growth.
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A similar arrangement was found in the primitive Labyrinthodonts, but in the evolutionary line that led to reptiles (and hence, also to mammals and birds), the intercentrum became partially or wholly replaced by an enlarged pleurocentrum, which in turn became the bony vertebral body. In most ray-finned fishes, including all teleosts, these two structures are fused with, and embedded within, a solid piece of bone superficially resembling the vertebral body of mammals. In living amphibians, there is simply a cylindrical piece of bone below the vertebral arch, with no trace of the separate elements present in the early tetrapods. In cartilaginous fish, such as sharks, the vertebrae consist of two cartilaginous tubes.
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The electric rays are a group of rays, flattened cartilaginous fish with enlarged pectoral fins, composing the order Torpediniformes. They are known for being capable of producing an electric discharge, ranging from 8 to 220 volts, depending on species, used to stun prey and for defense.Martin, R. Aidan. Electric Rays.
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Similar organs with similar characteristics are found in other fishes, for example the andropodium in the Hemirhamphodon or in the Goodeidae.Helfman G, Collette BB, Facey DH and Bowen BW (2009) The Diversity of Fishes: Biology, Evolution, and Ecology p. 35, Wiley-Blackwell. . Claspers are found on the males of cartilaginous fishes.
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Shark skeletons are very different from those of bony fish and terrestrial vertebrates. Sharks and other cartilaginous fish (skates and rays) have skeletons made of cartilage and connective tissue. Cartilage is flexible and durable, yet is about half the normal density of bone. This reduces the skeleton's weight, saving energy.
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In mammals, the fibrillar collagens involved in the formation of cross-striated fibrils are types I–III, V, and XI. Type II and type XI collagens compose the fibrils present in cartilage. These can be distinguished from collagens located in non-cartilaginous tissues, which include type I, III, and V collagens.
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The pathophysiology of MTD is multifactorial. Voice production requires the coordination of multiple muscles and other structures in the larynx. Multiple factors cause the muscles of the larynx to become tense. This changes the position of the larynx and affects the cartilaginous structures within the larynx leading to abnormal phonation.
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Histological observations confirm anatomical evidence of neoteny in branchiosaurids. Skeletochronological analysis allows for the identification of sexual maturity (i.e. when the distance between lines of arrested growth (LAGs) suddenly decreases). In Apateon specimens determined to be sexually mature, the cartilaginous Katschenko's line can be observed when perichondral ossification is complete.
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Petalodus ohioensis Petalodontiformes ("thin-plate teeth") is an extinct order of marine cartilaginous fish related to modern day chimaera found in what is now the United States of America and Europe.Lund, Richard, E. D. Grogan, and M. Fath. "On the relationships of the Petalodontiformes (Chondrichthyes)." Paleontological Journal 48.9 (2014): 1015-1029.
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The blackchin guitarfish (Rhinobatos cemiculus or sometimes Glaucostegus cemiculus) is a species of cartilaginous fish in the family Rhinobatidae. It is native to the eastern Atlantic Ocean and the Mediterranean Sea. It is a bottom-dwelling fish feeding on crustaceans, other invertebrates and fish. The females give birth to live young.
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In turn, the bony fish came from the Acanthodii class of bony and cartilaginous fish. The common name of M. albus is somewhat of a misnomer, as the Asian swamp eel is not an eel, per se. Eels are of the order Anguilliformes, while M. albus is of the order Synbranchiformes.
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The stems of the plant grow up to 30 or 40 cm long. Leaves are decussate, arranged oppositely in perpendicular pairs along the stems. The leaves are oval with thick, whitish, cartilaginous margins and measure up to 2 cm long. Flowers occur in leaf axils singly or in short, spikelike inflorescences.
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Congenital cartilaginous rest of the neck is a minor and very rare congenital cutaneous condition characterized by branchial arch remnants that are considered to be the cervical variant of accessory tragus. It resembles a rudimentary pinna that in most cases is located in the lower anterior part of the neck.
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Troodon had crista supporting its tympanic membrane that were ossified at least in their dorsal and ventral regions and their remaining portions either cartilaginous or too delicate to be preserved. The metotic strut of Troodon was "laterally hypertrophied". This condition resembles that of Dromaeosaurus and primitive birds like Archaeopteryx and Hesperornis.
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The shaft is broad in dimension and connects via cartilaginous linkages to three lateral segments. The glans penis has a dorsal lobe elevated above a ventral rim. The rim has spiny fingerlike processes, but not the dorsal lobe. An rod shaped os clitoridis may be present, in front of the urethra.
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The most distinctive feature of T. marauna is a prominent fleshy (possibly cartilaginous) extension at the tip of the upper jaw, in which approximately 15 slender teeth are loosely embedded. Another, toothless, extension is present at the tip of the lower jaw. T. marauna is mostly light brown to gray- brown.
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Stewart J. R. (1997): Morphology and evolution of the egg of oviparous amniotes. In: S. Sumida and K. Martin (ed.) Amniote Origins-Completing the Transition to Land (1): 291–326. London: Academic Press. In addition to bony fish and cephalopods, macrolecithal eggs are found in cartilaginous fish, reptiles, birds and monotreme mammals.
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Squalomorphii is a superorder of cartilaginous fishes, generally characterized by lacking traits such as an anal fin, nictitating membrane, or suborbital shelves in the cranium. Also called squalea, or squalean sharks. There are about 163 living species in 11 families. Squalean sharks are divided into four orders: the Hexanchiformes, Squaliformes, Squatiniformes, and Pristiophoriformes.
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The dentary rings are counted in much the same way a tree is aged. Dentary studies suggest that some individuals can live 60 years or longer, and that females typically live longer and grow larger than males. American paddlefish are smooth-skinned and almost entirely cartilaginous. Their eyes are small and directed laterally.
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Ichthyology is the branch of zoology devoted to the study of fish, including bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of October 2016, with approximately 250 new species described each year.FishBase: October 2016 Update. Retrieved 7 October 2016.
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Members of the genus Leiopelma exhibit a number of basal traits that separate them from most other species. These traits include: vestigial tail-wagging muscles, cartilaginous inscriptional ribs, the presence of amphicoelous vertebrae, and nine presachral vertebrae (most frogs have eight). In addition, Leiopelma lack external ear drums and produce only limited vocalizations.
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Extraskeletal myxoid chondrosarcoma (EMC) is a rare low-grade malignant mesenchymal neoplasm of the soft tissues, that differs from other sarcomas by unique histology and characteristic chromosomal translocation. There is an uncertain differentiation (there is no evidence yet showing that EMC exhibits the feature of cartilaginous differentiation) and neuroendocrine differentiation is even possible.
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Ash (1972), pp. 124–128. The fauna found in Dockum Group confirm that there were lakes and/or rivers containing fish such as the cartilaginous Xenacanthus, the lobe-finned Chinlea and the dipnoan Ceratodus.Chatterjee (1985), p. 434. On the shores of these rivers lived labyrinthodonts (Latiscopus) and reptiles such as Malerisaurus and Trilophosaurus.
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The plant tissue varies in color from red to peach, the texture is fleshy and cartilaginous, and the shape is flat and leaf-like, with irregular deep forking divisions. The edges often grow many branchlets of uneven lengths. The surfaces of older individuals will grow warty or spiky protuberances. The morphology is variable.
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P53, p63, and p73 have similar features in their gene structures and functions but have also diverged evolutionarily. The p53 family evolved from a p63/p73 ancestor gene in invertebrates. P53 diverged from p63/p73 with a gene duplication in the cartilaginous fish. P63 and p73 differentiated from each other in bony fish.
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A new species of Graneledone (Cephalopoda:Octopodidae) from the Southweat Atlantic Ocean. J.Mollus.Stud.66(4):5 43-549. G. yamana physically resembles the species Graneledone verrucosa, except the cartilaginous warts on the body cavities of both these species differ. G. verruscosa is also found in the North Atlantic Ocean instead of the South.
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In most animals, the articular bone is connected to two other lower jaw bones, the suprangular and the angular. Developmentally, it originates from the embryonic mandibular cartilage. The most caudal portion of the mandibular cartilage ossifies to form the articular bone, while the remainder of the mandibular cartilage either remains cartilaginous or disappears.
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A stingray's barb (ruler in cm). The barb is covered with rows of flat spines, composed of vasodentin. Vasodentin is an incredibly strong cartilaginous material which can easily cut through flesh. The undersides of the spines contain two longitudinal grooves which run along the length of the spine and enclose venom-secreting cells.
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This list of fossil fishes described in 2019 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes of every kind that were described during the year 2019, as well as other significant discoveries and events related to paleoichthyology that occurred in 2019.
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Brevitrygon walga, the dwarf whipray or mangrove whipray, is a small stingray, a cartilaginous fish in the family Dasyatidae. It is a demersal fish and is found over the continental and insular shelf of the west central Pacific Ocean where it is heavily fished. The IUCN has assessed it as being "near- threatened".
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Female idiacanthidae have a dorsal fin with a long base anterior to its midbody. Females have black skin while male idiacanthidae are dark brown. For I. fasciola, females have a well-ossified skeleton while males have a cartilaginous skeleton. There are also the aforementioned differences of teeth, barbel, and black vs brown color.
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What was initially believed to be a bony sternum turned out to be part of the coracoid, but a cartilaginous sternum may have been present. Only the front of its face is missing. It has been used as the basis for a distinct species, A. bavarica,Wellnhofer, Peter. Archaeopteryx. Der Urvogel Von Solnhofen.
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Fibrocartilage consists of a mixture of white fibrous tissue and cartilaginous tissue in various proportions. It owes its inflexibility and toughness to the former of these constituents, and its elasticity to the latter. It is the only type of cartilage that contains Type I collagen in addition to the normal type II.
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Asclepiades of Bithynia is credited with being the first person who proposed bronchotomy as a surgical procedure, though he never attempted to perform one. Aretaeus of Cappadocia thought the procedure dangerous even as a remedy for choking, since the resulting incision "would not heal, as being cartilaginous"; Caelius Aurelianus also rejected its usefulness.
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The holotype and paratype of Q. rostrata are two exquisitely preserved specimens both featuring a domed cranium and a curved rostrum presenting a "dolphin-like profile." The researchers' cladistic diagram shows Q. rostrata as the sister taxon of Entelognathus, Janusiscus and the crown gnathostomes (i.e., bony and cartilaginous fishes and their descendants).
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They are a silvery color and have a rough skin texture. The mola is the heaviest of all the bony fish, with large specimens reaching vertically and horizontally and weighing nearly . Sharks and rays can be heavier, but they are cartilaginous fish. Mola are found in temperate and tropical oceans around the world.
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This list of fossil fishes described in 2020 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes of every kind that were described during the year 2020, as well as other significant discoveries and events related to paleoichthyology that occurred in 2020.
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This cut of meat actually has no bones, but instead has "buttons" of cartilaginous material with meat attached. Rib tips (or brisket) are found at the bottom of the spare ribs by the sternum. The rib tips have a high proportion of cartilage. The rib tips give the spare ribs a rounded appearance.
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The chondrocranium (or cartilaginous neurocranium) is the primitive cartilaginous skeletal structure of the fetal skull that grows to envelop the rapidly growing embryonic brain.Salentijn, L. Biology of Mineralized Tissues: Prenatal Skull Development, Columbia University College of Dental Medicine post-graduate dental lecture series, 2007 The chondrocranium in different species can vary greatly, but in general it is made up of five components, the sphenoids, the mesethmoid, the occipitals, the optic capsules and the nasal capsules. In humans, the chondrocranium begins forming at 28 days from mesenchymal condensations and is fully formed between week 7 and 9 of fetal development. While the majority of the chondrocranium is succeeded by the bony skull in most higher vertebrates, some components do persist into adulthood.
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Duffinselache (Duffin's shark) is an extinct genus of basal selachimorph elasmobranchii cartilaginous fish known from the Late Triassic (Rhaetian stage) of England. It was first named by Duffin in 1998 as a species of Polyacrodus. Plamen S. Andreev and Gilles Cuny in 2012 reassigned to its own genus, and its type species is Duffinselache holwellensis.
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Sebacina is a genus of fungi in the family Sebacinaceae. Its species are mycorrhizal, forming a range of associations with trees, orchids, and other plants. Basidiocarps (fruit bodies) are produced on soil and litter, sometimes partly encrusting stems of living plants. The fruit bodies are cartilaginous to rubbery-gelatinous and variously effused to coral-shaped.
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Diving Weddell seals Before diving, pinnipeds typically exhale to empty their lungs of half the airRiedman, p. 25. and then close their nostrils and throat cartilages to protect the trachea.Berta, p. 69. Their unique lungs have airways that are highly reinforced with cartilaginous rings and smooth muscle, and alveoli that completely deflate during deeper dives.
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Biology, p. 669\. McGraw-Hill Education, New York. . The brain is protected in a cartilaginous cranium. The giant nerve fibers of the cephalopod mantle have been widely used for many years as experimental material in neurophysiology; their large diameter (due to lack of myelination) makes them relatively easy to study compared with other animals.
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The lateral half of the great wing of the sphenoid bone articulates, by means of a synchondrosis, with the petrous part of the temporal bone. Between these two bones on the under surface of the skull, is a furrow, the 'sulcus of auditory tubule, for the lodgement of the cartilaginous part of the auditory tube.
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The disparity between the maturation size and the maximum size is usually large for a cartilaginous fish, and it is possible that the specimens currently identified as the Coral Sea stingaree actually represent distinct species, one large and one small. However, the presumed large and small forms cannot be distinguished by morphological or meristic traits.
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Crustospathula species are crustose with stalked and cartilaginous soredia that are labriform (lip-shaped) or crenately (scalloped) lobed. The ascospores are rod-shaped and often curved or bent. They contain between 0 and 3 septa, and measure 20–25 by 0.8–1.5 um. The lichens contain the secondary compounds atranorin and 2'-O-methylperlatolic acid.
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In modern amniotes (including mammals), the middle ear collects airborne sounds through an eardrum and transmits vibrations to the inner ear via thin cartilaginous and ossified structures. These structures usually include the stapes (a stirrup-shaped auditory ossicle). Early tetrapods likely did not possess eardrums. Eardrums appear to have evolved independently three to six times.
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Camouflaged round ribbontail ray Myliobatiformes is one of the four orders of batoids, cartilaginous fishes related to sharks. They were formerly included in the order Rajiformes, but more recent phylogenetic studies have shown the myliobatiforms to be a monophyletic group, and its more derived members evolved their highly flattened shapes independently of the skates.
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Skates are cartilaginous fish belonging to the family Rajidae in the superorder Batoidea of rays. More than 150 species have been described, in 17 genera.LAST, P.R. & SÉRET, B. & STEHMANN, M.F.W. & WEIGMANN, S. (2016) Skates, Family Rajidae. In: Last, P.R., White, W.T., Carvalho, M.R. de, Séret, B., Stehmann, M.F.W & Naylor, G.J.P (Eds.) Rays of the World.
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Skates are primarily found from the intertidal down to depths greater than . They are most commonly found along outer continental shelves and upper slopes. They are typically more diverse at higher latitudes and in deep-water. In fact, skates are the only cartilaginous fish taxon to exhibit more diversity of species at higher latitudes.
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For example, if an extra bone formed on the ankle, it might grow up to the shin. When used in the phrases "cartilaginous exostosis" or "osteocartilaginous exostosis", the term is considered synonymous with osteochondroma. Some sources consider the two terms to mean the same thing even without qualifiers, but this interpretation is not universal.
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Edaphodon was a prehistoric chimaeriform fish genus of the family Callorhinchidae (sometimes assigned to Edaphodontidae). So, Edaphodon was a type of rabbitfish, a cartilaginous fish related to sharks and rays. Edaphodon has under 15 known species, all of which are extinct. This genus appeared in Aptian age (end of lower Cretaceous) and vanished in Pliocene.
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A Smooth dogfish (left) and a Little Skate (right), two cartilaginous fish at the Nantucket Aquarium in 2013. The aquarium's highlights include a touch tank which is overlooked by the small aquarium gift shop. The touch tank houses crabs, fish (particularly flounder), shrimp, clams, and snails, including a large, predatory snail called a moon snail.
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Turtles are reptiles of the order Testudines. They are characterized by a special bony or cartilaginous shell developed from their ribs that acts as a shield. "Turtle" may refer to the order as a whole (American English) or to fresh-water and sea-dwelling Testudines (British English). Testudines includes both extant (living) and extinct species.
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Each rib is thinnest in the middle. A jumble of thin bones in the middle part of the body are probably the remains of gastralia (belly ribs) and components of a cartilaginous sternum. The sacral vertebrae are partially fused to each other. Most of the caudal vertebrae possess tapering ribs which are flattened from the side.
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It is an evergreen perennial growing to tall by wide. The leaves are obovate and stalkless, with a cartilaginous edge, all growing in a basal rosette, and sometimes covered in a mealy white bloom. The yellow flowers grow in clusters on long stalks. The specific epithet auricula means "ear-shaped", and refers to the shape of the leaves.
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Parexus is an extinct genus of acanthodian fish. Acanthodians are often referred to as ‘spiny sharks’, although acanthodians are not true sharks and evolved perhaps 50 million years earlier than sharks. Acanthodians share several features with bony fish and cartilaginous fish; they often have spines supporting their fins. Parexus is recognised by its large anterior dorsal fin spine.
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Placement of Jacobson's organ in a snake The VNO is found at the base of the nasal cavity. It is split into two, being divided by the nasal septum, with both sides possessing an elongated C-shaped, or crescent, lumen. It is encompassed inside a bony or cartilaginous capsule which opens into the base of the nasal cavity.
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The head was small. It had small leaf-shaped cheek teeth (triangular and with small ridges and denticles lining the front and back edges), and premaxillary teeth with less ornamentation. Like several other neornithischian dinosaurs, such as Hypsilophodon, Thescelosaurus, and Talenkauen, Nanosaurus had thin plates lying along the ribs. Called intercostal plates, these structures were cartilaginous in origin.
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Siksika ottae is an extinct prehistoric cartilaginous fish, lived during the Upper Mississippian. It has been discovered at the well known, Carboniferous- aged Bear Gulch Formation (Montana, United States). It is known primarily from fossil teeth, but also from partial neurocranium and mandibles which hint a close relationship to coeval petalodontiform sharks Janassa and Netsepoye. Dentition is generally heterodont.
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In crocodilians, the columella arises from a proximal and a distal component which develop into the columella and extracolumella, respectively. It is typically trifurcated, with three finger-like projections supporting it against the tympanic membrane. The extracolumella remains cartilaginous while the columella ossifies during development. The connection between the columella and extracolumella remains flexible over the animal's lifetime.
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Its chondrocranium, the cartilaginous skull, would have had a blockier and more robust appearance than that of the great white. Its fins were proportional to its larger size. Some fossil vertebrae have been found. The most notable example is a partially preserved vertebral column of a single specimen, excavated in the Antwerp Basin, Belgium, in 1926.
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Elements of the cartilaginous viscerocranium (i.e., splanchnocranial elements), such as the hyoid bone, are sometimes considered part of the facial skeleton. The ethmoid bone (or a part of it) and also the sphenoid bone are sometimes included, but otherwise considered part of the neurocranium. Because the maxillary bones are fused, they are often collectively listed as only one bone.
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Bradyodonti is an order of cartilaginous fishes (class Chondrichthyes) that lived in the Paleozoic Era. They first appeared toward the end of the Devonian Period, were present through the Carboniferous Period, and became extinct by the end of the Permian Period. Most Bradyodonti fossils consist of jaws and teeth. These indicate that Bradyodonti ate mollusks and other shelled invertebrates.
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The otoplastic surgeon corrects the defect or deformity by creating an external ear that is of natural proportions, contour, and appearance, usually achieved by the reshaping, the moving, and the augmenting of the cartilaginous support framework of the pinna. Moreover, the occurrence of congenital ear deformities occasionally overlaps with other medical conditions (e.g. Treacher Collins syndrome and hemifacial microsomia).
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The Aspidogastrea (Ancient Greek: ' “shield”, ' “stomach/pouch”) is a small group of flukes comprising about 80 species. It is a subclass of the trematoda, and sister group to the Digenea. Species range in length from approximately one millimeter to several centimeters. They are parasites of freshwater and marine molluscs and vertebrates (cartilaginous and bony fishes and turtles).
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The four boat-shaped, about 3 millimeter long bracts male flowers grow together up to half their length and cartilaginous in the upper area. The four stamens protrude beyond the chalice and "explode" when shaken. The female flowers are almost seated in the cymose inflorescences. In the female flowers a rudimentary conical carpel is present in each case.
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Binder's Syndrome/Binder Syndrome (Maxillo-Nasal Dysplasia) is a developmental disorder primarily affecting the anterior part of the maxilla and nasal complex (nose and jaw). It is a rare disorder and the causes are unclear. The characteristics of the syndrome are typically visible. The syndrome involves hypoplasia of variable severity of cartilaginous nasal septum and premaxilla.
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They have a small frontal sinus and global facial imbalance. Treatment is encouraged as early as possible with posteroanterior traction on the maxilla and, at about age 8, reinsertion of the nasolabial muscles onto the anterior border of the cartilaginous system. Many who have a severe case of the disorder undergo plastic surgery or orthodontic treatment for cosmetic reasons.
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Leaf detail Flower detail The plants form stemless rosettes of up to 30 cm wide. Smaller suckers sometimes offshoot from the main stem. The long sharp, triangular leaves are dark brownish green with white linear spots and cartilaginous margins. Tall, very thin multi-branched inflorescences appear from January to March, with small sparse pale pink and sometimes bluish flowers.
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A great white shark at Isla Guadalupe, Mexico The following outline is provided as an overview of and topical guide to sharks: Sharks (superorder Selachimorpha) are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 440 million years ago, before the time of the dinosaurs.
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Harpagofututor is an extinct genus of cartilaginous fish from the Mississippian of North America. It was an eel-shaped fish with almost no scales. About eight inches (20 cm) long, it swam with some help from its fins, but also relied on whole-body locomotion to move. The fish also had teeth sufficient for eating shellfish.
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The Eugeneodontida is an extinct and poorly known order of bizarre cartilaginous fishes. They possessed a unique "tooth-whorl" on the symphysis of the lower jaw and pectoral fins supported by long radials. The palatoquadrate was either fused to the skull or reduced. Now determined to be within the Holocephali, their closest living relatives are ratfish.
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They open as the mouth closes, causing the pressure inside the fish to drop. Water then flows towards the lower pressure across the fish's gill lamellae, allowing some oxygen to be absorbed from the water. In cartilaginous ratfishes, they present soft and flexible opercular flaps. Sharks, rays and relatives such as elasmobranch fishes lack the opercular series.
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The dermis is covered with separate dermal placoid scales. They have a cloaca into which the urinary and genital passages open, but not a swim bladder. Cartilaginous fish produce a small number of large, yolky eggs. Some species are ovoviviparous and the young develop internally but others are oviparous and the larvae develop externally in egg cases.
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The bullseye round stingray (Urobatis concentricus), also known as the reticulated round ray, or spot-on-spot round ray, is a species of cartilaginous fish in the family Urotrygonidae. It is endemic to Mexico. Its natural habitats are shallow seas, subtidal aquatic beds, coral reefs, estuarine waters, intertidal marshes, and coastal saline lagoons. It is threatened by habitat loss.
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Occasionally the bones of vertebrates are found, as well as the cartilaginous vertebrae of sharks. Fish scales and plant leaves are sometimes found as well (Wade 1926). The Coon Creek Formation has one of the highest densities of fossil in Eastern North America. Crustacean fossils have also been unearthed in the Coon Creek Formation as well.
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The rock dove's operculum is a mass at the base of the bill. The nares of some birds are covered by an operculum (plural opercula), a membraneous, horny or cartilaginous flap.Gill (1995), p. 117. In diving birds, the operculum keeps water out of the nasal cavity; when the birds dive, the impact force of the water closes the operculum.
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The deep auricular artery often arises in common with the anterior tympanic artery. It ascends in the substance of the parotid gland, behind the temporomandibular articulation, pierces the cartilaginous or bony wall of the external acoustic meatus, and supplies its cuticular lining and the outer surface of the tympanic membrane. It gives a branch to the temporomandibular joint.
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Typical gross appearance of a tubular cartilaginous construct engineered from amniotic mesenchymal stem cells Mesenchymal stem cells can be activated and mobilized if needed but their efficiency, in the case of muscle repair for example, is currently quite low. Further studies into the mechanisms of MSC action may provide avenues for increasing their capacity for tissue repair.
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The undulate ray (Raja undulata) is a species of ray and cartilaginous fish found in the Mediterranean and East Atlantic from southern Ireland and England to the Gulf of Guinea. It is found in areas with mud or sand, and may occur as deep as , though it prefers shallower depths. It is considered endangered due to overfishing.
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The pubic symphysis is a secondary cartilaginous joint between the left and right superior rami of the pubis of the hip bones. It is located in front of and below the urinary bladder. In males, the suspensory ligament of the penis attaches to the pubic symphysis. In females, the pubic symphysis is close to the clitoris.
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Phylogenetically, they are the oldest group of living jawed Chondrichthyes. They possess the same cartilaginous skeleton seen in sharks but are considered holocephali to distinguish them from the shark and ray categorization. Because of this, they provide a useful research organism for studying the early development of the jawed characteristic. Among the Chondrichthyes genome, Callorhinchus has the smallest genome.
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Its wing membranes are black. Its ears, tragi (the cartilaginous projections in front of the ear openings), nose-leaf, and lips are a bright, yellowish orange. Its yellow-orange pigmentation is due to large concentrations of carotenoids, particularly xanthophyll. It is the first mammal known to have enough carotenoids in its skin to generate conspicuous color.
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Venom is found in some 200 cartilaginous fishes, including stingrays, sharks, and chimaeras; the catfishes (about 1000 venomous species); and 11 clades of spiny-rayed fishes (Acanthomorpha), containing the scorpionfishes (over 300 species), stonefishes (over 80 species), gurnard perches, blennies, rabbitfishes, surgeonfishes, some velvetfishes, some toadfishes, coral crouchers, red velvetfishes, scats, rockfishes, deepwater scorpionfishes, waspfishes, weevers, and stargazers.
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Members of this small group have either a single divided sucker or a row of suckers that cover the underside. They infest the guts of bony or cartilaginous fish, turtles, or the body cavities of marine and freshwater bivalves and gastropods. Their eggs produce ciliated swimming larvae, and the life cycle has one or two hosts.
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But bony fish that breathe through their skin or lungs evolved into living vertebrates, and are more closely related to terrestrial vertebrates than to sharks and other cartilaginous fish. Another example is thermo-regulation in reptilia and birds. Reptilia are ectothermic (coldblooded) and birds are endothermic (warmblooded). This is plesiomorphic for birds and plesiomorphic for reptiles.
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The brain of Pawpawsaurus is long and wide. The inner ear is also similar to ankylosaurians to the exclusion of Kunbarrasaurus, being tall and wide at the level of the semicircular canals. The nasal cavities of Pawpawsaurus resemble that of Panoplosaurus and Euoplocephalus, although the thin dividing medians are not preserved as they were likely cartilaginous.
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This breed has been a native breed which formed due to natural selection and a bit of human interference. The coats of Kurdish mastiffs can be yellow, white, red, burgundy, blue and black. The breed has loose skin, large dewlaps, and non- cartilaginous (soft and floppy) ears. The breed is longer and stronger than the other Asian mastiffs.
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A heavy-chain shark antibody (left) and a heavy-chain camelid antibody (middle) in comparison to a common antibody (right). Heavy chains are shown in a darker shade, light chains in a lighter shade. The immunoglobulin new antigen receptor (IgNAR) of cartilaginous fishes (for example sharks) is a heavy-chain antibody. IgNAR shows significant structural differences to other antibodies.
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This species becomes more active at night, swimming onto the reef to hunt. The tasselled wobbegong feeds on bony and cartilaginous fishes, crustaceans, and cephalopods. Its capacious mouth allows sizeable prey to be swallowed, with one documented case of a long individual consuming a long brownbanded bamboo shark (Chiloscyllium punctatum). During daytime, this species is an opportunistic ambush predator.
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The nasal passage contains nine or ten air sacs, which are capable of sealing off all air within the passage. Behind these are an additional set of vomeronasal sacs. The trachea, however, is short, with only four cartilaginous rings. The stomach has three chambers, with no caecum, and no distinct difference between the small and large intestines.
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The placoderm claspers are not homologous with the claspers in cartilaginous fishes. The similarities between the structures has been revealed to be an example of convergent evolution. While the claspers in cartilaginous fishes are specialized parts of their paired pelvic fins that have been modified for copulation due to changes in the hox genes hoxd13, the origin of the mating organs in placoderms most likely relied on different sets of hox genes and were structures that developed further down the body as an extra and independent pair of appendages, but which during development turned into body parts used for reproduction only. Because they were not attached to the pelvic fins, as are the claspers in fish like sharks, they were much more flexible and could probably be rotated forward.
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The diameter of the tube is not uniform throughout, being greatest at the pharyngeal opening, least at the junction of the bony and cartilaginous portions, and again increased toward the tympanic cavity; the narrowest part of the tube is termed the isthmus. The position and relations of the pharyngeal opening are described with the nasal part of the pharynx. The mucous membrane of the tube is continuous in front with that of the nasal part of the pharynx, and behind with that of the tympanic cavity; it is covered with ciliated pseudostratified columnar epithelia and is thin in the osseous portion, while in the cartilaginous portion it contains many mucous glands and near the pharyngeal orifice a considerable amount of adenoid tissue, which has been named by Gerlach the tube tonsil.
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Each is on a stalk of 1–1½ cm (0.4–0.6 in) long. The common base of the flowers in the same head is flattened and 6–7 mm (0.24–0.28 in) wide. The bracts that subtend the head have a pointy tip and are lance-shaped to oval, 5–7 mm (0.20–0.28 in) long and 3–5 mm (0.12–0.20 in) wide, overlapping, cartilaginous in consistency, densely silky, the tip slightly hooked and thickened. The bract that subtends each flower individually is rectangular, about 5 mm (0.20 in) long and 2 mm (0.08 in) wide, embraces the flower at its base (or obtrullate), cartilaginous in consistency, densely softly hairy, the tip hooked. The initially yellow, 4-merous perianth is 16–18 mm (0.64–0.72 in) long.
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The mouth is underneath, framed by large and protrusible lips covered with many papillae. The inner margin of the lower lip has two semicircular bare areas, and a cartilaginous plate used for scraping. Just above the 9-rayed pelvic fins there are small protrusions on each side. Length ranges up to 25 cm, with a length under 20 cm typical.
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The stipe attachment is adnate or arcuate, but later develops a pronounced decurrent tooth. The decurrent tooth occasionally separates from the stipe and forms a collar around it. The stipe is long, thick, equal in width throughout, hollow, cartilaginous, and brittle. The stipe surface is smooth or polished, with the apex initially faintly pruinose (as if covered with a fine whitish powder).
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Fish fall into two main groups: fish with bony internal skeletons and fish with cartilaginous internal skeletons. Fish anatomy and physiology generally includes a two-chambered heart, eyes adapted to seeing underwater, and a skin protected by scales and mucous. They typically breathe by extracting oxygen from water through gills. Fish use fins to propel and stabilise themselves in the water.
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This list of fossil fish described in 2018 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fish, bony fish, and other fish of every kind that are scheduled to be described during the year 2018, as well as other significant discoveries and events related to paleontology of fish that are scheduled to occur in 2018.
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Skeleton of a ray-finned fish Bony fishes form a taxonomic group called Osteichthyes. They have skeletons made of bone, and can be contrasted with cartilaginous fishes which have skeletons made of cartilage. Bony fishes are divided into ray-finned and lobe-finned fish. Most fish are ray-finned, an extremely diverse and abundant group consisting of over 30,000 species.
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Sharks possess a heterocercal caudal fin in which the dorsal portion is usually noticeably larger than the ventral portion. This is because the shark's vertebral column extends into that dorsal portion, providing a greater surface area for muscle attachment. This allows more efficient locomotion among these negatively buoyant cartilaginous fish. By contrast, most bony fish possess a homocercal caudal fin.
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This shark typically reaches lengths of . The pigeye shark is an apex predator that mostly hunts low in the water column. It has a varied diet, consisting mainly of bony and cartilaginous fishes and also including crustaceans, molluscs, sea snakes, and cetaceans. This species gives birth to live young, with the developing embryos sustained to term via a placental connection to their mother.
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Nocturnally active, the prickly shark rests during the day in deeper offshore waters and performs a diel migration to shallower inshore waters at dusk. Individual sharks have a small home range and tend to remain within a given local area. This species consumes a variety of bony and cartilaginous fishes, and cephalopods. Since it moves slowly, it may use suction to capture prey.
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Ellis, Richard and John E. McCosker. 1995. Great White Shark. Stanford University Press, Among living cartilaginous fish, only the whale shark (Rhincodon typus), the basking shark (Cetorhinus maximus) and the giant manta ray (Manta birostris), in that order, are on average larger and heavier. These three species are generally quite docile in disposition and given to passively filter-feeding on very small organisms.
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Sebacina schweinitzii is a lookalike species. The "crested coral" (Clavulina cristata, edible) is similar in appearance to R. kunzei, but its branches have fringed, feathery tips. The "jellied false coral" (Tremellodendron pallidum, edible) has whitish, tough, cartilaginous branches with blunt tips. Ramariopsis lentofragilis (poisonous) is an eastern North American lookalike that causes severe abdominal pain, general weakness, and pain under the sternum.
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Hybrids between the Australian blacktip shark and the common blacktip shark, comprising both F1 and backcrossed individuals, have been discovered all along the eastern coast of Australia. Despite the widespread incidence of hybridization, there is no evidence that the two parental lineages are merging and the mechanisms preventing introgression are unclear. This is the first confirmed case of hybridization among cartilaginous fishes.
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The rest of the skeleton is cartilaginous. The hyperostosis provides additional support to the pterygiophores during movement. The presence of hyperostosis varies among R. russelii of different ages and sizes; it is present in most large adult fish, and many smaller fish lack these regions of swollen bones. R. russeliis flaccid skeleton lacks mineralization, which is advantageous in maintaining buoyancy in deep waters.
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However, the best preserved specimens of Michiganian acanthodians reveal large eyed generalists who ate plankton in the mid-level of the water column using teeth with multiple points. The Pleistocene American mastodon with a human to scale. Sharks swam over Michigan during the Devonian. Since shark skeletons were cartilaginous and lacked hard parts conducive to fossilization, typically only their spines and teeth remain.
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Seas continued to cover the state into the Carboniferous period. At that time, the state was home to a bewildering array of cartilaginous fishes. Further into the Paleozoic, Mississippian brachiopods, bryozoans, and corals left behind fossils in the Bridger Range and at Shell Mountain south of Big Timber. Later in the Carboniferous, during the Pennsylvanian epoch, the sea began to retreat.
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The heavy scale armour of the early bony fishes would certainly weigh the animals down. In cartilaginous fishes, lacking a swim bladder, the open sea sharks need to swim constantly to avoid sinking into the depths, the pectoral fins providing lift. Another factor is oxygen consumption. Ambient oxygen was relatively low in the early Devonian, possibly about half of modern values.
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This combined with the West Indian Ocean coelacanth's large eyes aid seeing in dark water. Similar to cartilaginous fish, Latimeria chalumnae has a rectal gland, pituitary gland, pancreas, and spinal cord. To balance osmotic pressure, these fish adopt an efficient mechanism of osmoregulation by retaining urea in their blood. Latimeria chalumnae is ovoviviparous fish that retain their eggs internally until they hatch.
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The distal end has an articulation for an additional cartilaginous segment or series. Therefore, the difference in pelvic claspers between genders suggests that sexual dimorphism was already present in the arthrodires in the Devonian. Pelvic claspers have also been discovered in pyctodontid fossils suggesting homology. It is therefore suggested that pelvic claspers may characterise all of the pytodontids and arthrodires.
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Very little is known of the biology and behavior of the smalltooth sand tiger. It is an active predator of benthic bony fishes, invertebrates, and cartilaginous fishes. This species is thought to be ovoviviparous with oophagous embryos like other mackerel sharks. In contrast to its formidable size and appearance, this shark is harmless, having never been known to behave aggressively towards humans.
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Jiaodontus is an extinct genus of lonchidiid cartilaginous fish which existed in Liuhuanggou, Xinjiang Uyghur Autonomous Region, northwestern China, during the late Jurassic (Oxfordian age). Fossils have been found in the Qigu Formation, China. It was first named by Stefanie Klug, Thomas Tütken, Oliver Wings, Hans-Ulrich Pfretzschner and Thomas Martin in 2010 and the type species is Jiaodontus montaltissimus.
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The bony part forms the inner two thirds. The bony part is much shorter in children and is only a ring (annulus tympanicus) in the newborn. The layer of epithelium encompassing the bony portion of the ear canal is much thinner and therefore, more sensitive in comparison to the cartilaginous portion. Size and shape of the canal vary among individuals.
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This small red alga grows to a length of , erect from a disc shaped holdfast. It has a short, erect, terete stipe which expands as a flattened blade branching once or twice. The blades have a cartilaginous texture with a medulla of large cells within a cortex of one or two layers of small cells.Dixon, P.S. and Irvine, L.M. 1977.
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The small, stemless rosettes produce suckers that offshoot from the root, which can eventually form dense clumps. The sharp, triangular green leaves point slightly upwards and form three rows. The leaves are covered in linear white spots, and their narrow white cartilaginous margins are finely notched. Tall, very thin inflorescences appear in January and February, with small sparse pale pink flowers.
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They have no midrib but have two glands. When it blooms it produces single headed racemose inflorescences that form along an axis of . The spherical flower-heads contain 34 to 58 densely packed bright golden coloured flowers. After flowering crustaceous to cartilaginous linear shaped seed pods form that have a length of up to and a width of with longitudinally arranged seeds inside.
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Protospinax is an extinct genus of cartilaginous fish found in the Solnhofen limestones of southern Bavaria. It is a difficult taxon to accommodate in taxonomies. Formerly known from only two specimens, further museum specimens were discovered at the Museum of Comparative Zoology of Harvard University in the 1990s, having been misidentified as Squatina and Heterodontus. Protospinax was about 1.7 m in length.
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High latitude Chondrichthyans from the Late Devonian (Famennian) Witpoort formation of South Africa. Palaeontologische Zeitschrift 89, 147–169. Antarctilamna ultima are known from dorsal fin spines, teeth, cartilaginous elements, skin impressions and a small whole-bodied impressionGESS, R. W. & COATES, M. I. (2015b) High latitude Chondrichthyans from the Late Devonian (Famennian) Witpoort formation of South Africa. Palaeontologische Zeitschrift 89, 147–169.
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He died, after great sufferings, Oct 9th, 1872, from the effects of a cartilaginous tumor, which had been forming in the abdomen for more than three years. Tallman was married, May 17, 1842, to Frances M., daughter of Simon Hazleton, of Haddam. She died July 30, 1860. He was again married, April 27, 1864, to Hannah C. Graves, of Thompson, who survived him.
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Petalodontidae is an extinct family of marine cartilaginous fish related to modern day chimaera found in what is now the United States of America and Europe. With a very few exceptions, they are known entirely from teeth. All fossils range from the Carboniferous to the Permian, where they are presumed to have died out during the Permian/Triassic extinction event.
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The cartilage growth pattern is the same as in vertebrate cartilage. In gastropods, the interest lies on the odontophore, a cartilaginous structure that supports the radula. The most studied species regarding to this particular tissue is Busycotypus canaliculatus. The odontophore is a vesicular cell rich cartilage, consisting on vacuolated cells containing myoglobin, surrounded by a low amount of extra cellular matrix containing collagen.
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The Rhinochimaeridae, commonly known as long-nosed chimaeras, are a family of cartilaginous fish. They are similar in form and habits to other chimaeras, but have an exceptionally long conical or paddle-shaped snout. The snout has numerous sensory nerve endings, and is used to find food such as small fish. The first dorsal fin includes a mildly venomous spine, used in defense.
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T. pellucida. Unlike Cranchiinae , the other subfamily within Cranchiidae , Taoniinae all lack cartilaginous strips which extend back from the funnel-mantle point of fusion. Their funnels are free laterally, and they have one to three photophores on the eyes. The largest photophore is crescent-shaped for most genera, but it's triangular in Helicocranchia, a semicircle in Bathothauma, and circular in Sandalops.
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Much of the fish's structure is cartilaginous: it has 44 fewer bones than the zebrafish, and thus it is translucent and appears similar to larval forms. The natural diet of the dracula fish is unknown but in captivity it eats shrimp larvae, small nematodes and fish flakes. Close relatives of the fish feed upon small crustaceans and invertebrates.Jaggard, Victoria (2009-03-11).
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The ocellated eagle ray (Aetobatus ocellatus) is a species of cartilaginous fish in the eagle ray family Myliobatidae. It is found in the tropical Indo- West Pacific region.Kuhl, H. in van Hasselt, J.C. (1823) Uittreksel uit een’ brief van Dr. J. C. van Hasselt, aan den Heer C. J. Temminck. Algemein Konst- en Letter-bode I Deel (no. 20): 315–317.
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Gogoselachus was a diminutive shark-like fish that was a fast-swimming predator. It probably hunted other fish, such as placoderms and primitive bony fish. It had very unusual teeth, with large fangs surrounded by many small cusps; these jagged teeth were useful to snag its prey. Its scales resembled those of the spiny sharks, which were ancestral to all cartilaginous fish.
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All basal vertebrates breathe with gills. The gills are carried right behind the head, bordering the posterior margins of a series of openings from the esophagus to the exterior. Each gill is supported by a cartilaginous or bony gill arch. The gills of vertebrates typically develop in the walls of the pharynx, along a series of gill slits opening to the exterior.
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All basal vertebrates breathe with gills. The gills are carried right behind the head, bordering the posterior margins of a series of openings from the esophagus to the exterior. Each gill is supported by a cartilaginous or bony gill arch. The gills of vertebrates typically develop in the walls of the pharynx, along a series of gill slits opening to the exterior.
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They are considered to be vertical disc herniations through the cartilaginous vertebral body endplates. Schmorl's nodes can sometimes be seen radiographically, however they are more often seen on MRI, even when not visible on plain X-rays. They may or may not be symptomatic, and their etiological significance for back pain is controversial. In a study in Spine by Hamanishi, et al.
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Petalodus is an extinct genus of cartilaginous fish from the Pennsylvanian to the Permian,A. S. Woodward. 1889. Catalogue of the Fossil Fishes in the British Museum (Natural History) Part 1 1-613.Fossils (Smithsonian Handbooks) by David Ward (Page 198) known from subtriangular to rhomboidal teeth. The genus was named by Richard Owen in 1840 and the type species is Petalodus hastingsii.
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Paratrygon is a monotypic genus of the cartilaginous fish in the family of Potamotrygonidae. The sole currently recognized species is Paratrygon aiereba, the discus ray, manzana ray or ceja ray, from the Amazon and Orinoco basins in South America. Genetic and morphometric evidence suggests that P. aiereba as presently defined is a species complex.Frederico; Farias; Góes de Araújo; Charvet-Almeida; & Alves-Gomes (2012).
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The coracoid is robust and broad, measuring long and in height. The anterior edge is coarsely textured, likely for the articulation with cartilaginous tissue. A large foramen is located from the front to the back, probably acting as a channel for blood vessels and nerves. Diagram featuring the preserved tissue traces on femur and tibia Both femora were nicely preserved.
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Artiodus is an extinct genus of cartilaginous fish from the Permian period. The name comes from the type locality, the Arti River, combined with the Greek word for "tooth." It is currently monotypic, containing only the species A. prominens from the Early Permian of the Middle Urals of Russia. As with many Paleozoic chondrichthyian genera, its affinities are unclear at this time.
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About 700 living species of cephalopods have been identified. The nervous system of cephalopods is the most complex of all the invertebrates and their brain-to-body-mass ratio falls between that of endothermic and ectothermic vertebrates. The brain is protected in a cartilaginous cranium. The possibility that non-human animals may be capable of perceiving pain has a long history.
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Two other films are known, shot in London Zoo Thylacines, uniquely for marsupials, have largely cartilaginous epipubic bones with a highly reduced osseous element.Ronald M. Nowak, Walker's Marsupials of the World, JHU Press, 12/09/2005 This has been once considered a synapomorphy with sparassodonts,Marshall, L. Evolution of the Borhyaenidae, extinct South American predaceous marsupials. Berkeley: University of California Press, 1978.
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The central stoneroller is generally herbivorous, feeding primarily on algae scraped from rocks and logs with the cartilaginous ridge on its lower jaw. Young fish feed on rotifers, filamentous algae, and microcrustacea. It also feeds on detritus, diatoms, and occasionally aquatic insects. It is classified as a grazing minnow in its feeding behavior, and large schools of these fish often feed together.
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This operculum is cartilaginous and flexible. In 1961 Richter distinguished three types of the operculum in which the larval gyre of the operculum is apical. This gyre can be relatively somewhat larger (macro-oligogyre), smaller (micro-oligogyre) or a single gyre (monogyre). The eye morphology also consists of three types with differences in pigmented region between the lens and the retina.
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The little brown bat can be confused with the Indiana bat (M. sodalis) in appearance. The two can be differentiated by the little brown bat's lack of a keeled calcar--the cartilaginous spur on its uropatagium (the flight membrane between its hind legs). While it does have a calcar, that of the little brown bat is not nearly as pronounced.
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The proportional differences probably would have made it lighter, though, as less weight was concentrated near the thigh. Like Thescelosaurus, it had thin partly ossified cartilaginous (intercostal) plates along the ribs. The shoulder girdle was robust. Parksosaurus had at least eighteen teeth in the maxilla and about twenty in the lower jaw; the number of teeth in the premaxilla is unknown.
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The orthologous space for PROSER2 is fairly large, as 143 organisms are reported to have orthologs with the human PROSER2. The most distant ortholog of the human PROSER2 is the elephant shark, Callorhinchus milii. The most distant relatives of humans with PROSER2 are fish and sharks (cartilaginous fishes). For this same reason, it can be inferred that PROSER2 originated in vertebrates.
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MR appearance depends on composition of the intra-articular body. Entirely cartilaginous bodies will appear isointense to muscle on T1 and hyperintense to muscle on T2 weighted images. Partly calcified intra-articular bodies demonstrate foci of absent signal on all pulse sequences. Like CT arthrography, MR with gadolinium may be used to detect intra-articular bodies that have not yet calcified.
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The nasal passage contains nine or ten air sacs, which have a complicated structure, and are capable of sealing off all air within the passage. Behind these are an additional set of vomeronasal sacs. The trachea, however, is short, with only four cartilaginous rings. The stomach has three chambers, there is no caecum, and no distinct difference between the small and large intestines.
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After his wife's death, he married Catharina van Wapenveldt, with whom he had three children. He is believed to have died on 25 or 26 August 1627. Adam van Vianen's son Christian was considered to be his father's equal in skill, according to Joachim von Sandrart. He became known along with his brother for the auricular style of cartilaginous arabesques in baroque art.
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Cross-section of shoulder joint. The shoulder joint is a ball and socket joint between the scapula and the humerus. However the socket of the glenoid cavity of the scapula is itself quite shallow and is made deeper by the addition of the glenoid labrum. The glenoid labrum is a ring of cartilaginous fibre attached to the circumference of the cavity.
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The subclass Holocephali ("complete heads") is a taxon of cartilaginous fish in the class Chondrichthyes. The earliest fossils are of teeth and come from the Devonian period. Little is known about these primitive forms, and the only surviving group in the subclass is the order Chimaeriformes. This group includes the rat fishes in the genus Chimaera, and the elephant fishes in the genus Callorhinchus.
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Gliding is accomplished with the help of a parachute-like membrane called a patagium. Before taking off, flying squirrels bob and rotate their heads to gauge the route, and then leap into the air, spreading their patagia between cartilaginous spurs on their wrists and ankles. Small adjustments to these spurs give them some control over their speed and direction. Their flattened tails also aid in steering.
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The flesh is thin but pliant, grayish or pallid, cartilaginous, and lacks any distinctive odor and taste. substrate is covered with white hairs. The gills are attached by a tooth and are narrowly adnate, close to subdistant, narrow, equal, white or grayish, and with edges concolorous and often slightly eroded. Berkeley noted that the gills "vary a good deal in colour, and are sometimes very dark".
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Chondrocytes are only present in cartilage where they will produce cartilaginous matrix to maintain the structure. Sox9, L-Sox5 and Sox6 are needed for the osteochondroprogenitor to undergo chondrocytic differentiation. The transcription factor Sox9 can be found in multiple sites in the body (pancreas, central nervous system, intestines) and it is also found in all chondrocyte progenitor cells, suggesting that they are important in chondrogenesis.
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The eggs of fish and amphibians are jellylike. Cartilaginous fish (sharks, skates, rays, chimaeras) eggs are fertilized internally and exhibit a wide variety of both internal and external embryonic development. Most fish species spawn eggs that are fertilized externally, typically with the male inseminating the eggs after the female lays them. These eggs do not have a shell and would dry out in the air.
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161x161px Tadpoles of frogs and toads are usually globular, with a laterally compressed tail and internal gills. When first hatched, anuran tadpoles have external gills that are eventually covered by skin. Newly hatched tadpoles are also equipped with a cement gland which allows them to attach to objects. The tadpoles have a cartilaginous skeletons and a notochord which eventually develops into a proper spinal cord.
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Fruit bodies are typically cartilaginous or rubbery-gelatinous. In effused species (those that spread out loosely or flat), they are formed on the soil surface or in leaf litter, often encrusting fallen twigs and debris, sometimes encrusting the stem bases of living plants. In the type species, irregular or coral-like outgrowths may also be produced. In one species, bracket-like outgrowths are formed.
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Many shark teeth were associated with the extinct broad-tooth mako (Cosmopolitodus/Carcharodon hastalis) and megalodon, and the teeth of these two sharks were found near whale and seal remains. Eagle rays, sawfish, and angelsharks were other cartilaginous fish found. Most of the bony fish findings belonged to tunas and croakers. Livyatan and megalodon were likely the apex predators of this area during this time.
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The penis of the northern ghost bat does not employ a baculum, but rather, is composed of four cartilaginous bodies. It is about 5.5 mm long and 3.1 mm in diameter. The glans penis is white in color, and the prepuce is encased in a layer of short, fine hair. The testes are spindle-like in shape, symmetrical, and enclosed in a black tunica.
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The raw materials are prepared by different curing, acid, and alkali processes that are employed to extract the dried collagen hydrolysate. These processes may take several weeks, and differences in such processes have great effects on the properties of the final gelatin products. Gelatin also can be prepared at home. Boiling certain cartilaginous cuts of meat or bones results in gelatin being dissolved into the water.
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This sea was home to creatures including brachiopods, conodonts, crinoids, fish, and trilobites. During the Carboniferous the state was home to an unusual cartilaginous fish fauna. Later in the Paleozoic the sea began to withdraw, but with a brief return during the Permian. During the Triassic Montana was again covered in a sea whose inhabitants are the state's only known fossils from this time.
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Over two hundred kinds of Devonian marine life lived and died in the region. The familiar invertebrate groups including bryozoans, cephalopods, corals, gastropods, and pelecypods were all present. Notably these were joined by vertebrates, including placoderms from two different suborders, cartilaginous fishes and more. Although the Percha and Sly Gap are the same age, they don't share even a single individual species in common. Ophiacodon.
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The parasitic flatworms, which includes tapeworms, flukes and monogeneans, evolved from a single major lineage of free-living flatworm ancestors. The switch from a free-living to a parasitic lifestyle in the common ancestor of the parasitic flatworms involved a fundamental change in their tegument, which is found in all contemporary groups. Early-branching tapeworm groups are found in bony (e.g. teleost) and cartilaginous fishes (e.g.
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This gene is expressed in the avascular zone of prehypertrophic cartilage, and its expression decreases during chondrocyte hypertrophy and vascular invasion. The mature protein likely plays a role in endochondral bone development by permitting cartilaginous anlagen to be vascularized and replaced by bone. It may also be involved in the broad control of tissue vascularization during development. Alternative splicing results in multiple transcript variants encoding different isoforms.
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A. novae-zelandiae is a mat- forming/cushion-forming species and has fewer anthers (two anthers) than most Actinotus species. It is very like A. suffocatus but differs in that leaves are not clearly petiolate, the leaf apex is cartilaginous, and there are 5-6 bracts subtending the captula which are broadly ovate-triangular whereas A. suffocatus has 8-13 bracts which are narrowly triangular to oblong.
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This list of fossil fishes described in 2014 is a list of new taxa of placoderms, fossil cartilaginous fishes and bony fishess of every kind that have been described during the year 2014, as well as other significant discoveries and events related to paleontology of fishes that occurred in the year 2014. The list only includes taxa at the level of genus or species.
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Gill slits on a grey reef shark 4 = Gill slits on a lamprey Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks, and rays, as well as deep-branching vertebrates such as lampreys. In contrast, bony fishes have a single outer bony gill covering called an operculum.
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As in cartilaginous fish, the upper part of the duct forms the epididymis. In many species, the vas deferens ends in a small sac for storing sperm. The only vertebrates to lack any structure resembling a vas deferens are the primitive jawless fishes, which release sperm directly into the body cavity, and then into the surrounding water through a simple opening in the body wall.
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Ostmann's pad of fat (Ostmann fatty bodies) is a thin triangular layer of fatty tissue found in the Eustachian tube of the ear. It is seen on the lateral side of the cartilaginous part of Eustachian tube. Its function is to keep the tube closed and thereby protect it from reflux of nasopharyngeal secretions. The pad of fat is named after the German otologist Paul Ostmann.
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The spotted eagle ray (Aetobatus narinari) is a cartilaginous fish of the eagle ray family, Myliobatidae. As traditionally recognized, it is found globally in tropical regions, including the Atlantic, Pacific and Indian Oceans. Recent authorities have restricted it to the Atlantic (including the Caribbean and Gulf of Mexico) with other populations recognized as the ocellated eagle ray (A. ocellatus) and Pacific white-spotted eagle ray (A. laticeps).
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The silver lamprey is an eel-like fish with an attenuate body composed of 49–52 clearly defined segments (i.e. myomeres, between the last gill slit and the anus). Silver lampreys possess a cartilaginous skeleton, and adults generally grow to a length of 12 inches and are silvery or bluish in color when spawning. Prior to spawning adults are often a dull brown or tan color.
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Apart from diffuse abnormal cartilaginous calcification in pulmonary and :wikt:otic systems, patients develop significant arterial calcification throughout the body. Such calcification is concomitant with various diseases including diabetes, atherosclerosis, and kidney dysfunction, while patients with oral anticoagulant use have significant aortic valve and coronary artery calcification. Although not distinctive to KS, echocardiogram analysis has revealed right ventricular hypertrophy resulting in severe pulmonary artery hypertension in several cases.
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Fish are gill-bearing aquatic craniate animals that lack limbs with digits. They form a sister group to the tunicates, together forming the olfactores. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period.
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The book had four sections: an introduction to fish biology; cetaceans; cartilaginous fish (sharks and rays); and bony fish, the last group being further classified by the number and nature of their fins. 187 plates completed the work, their cost making the book a financial disaster for the Royal Society, which had largely funded its publication.Birkhead (2018) pp. 241–245.Jardine (1999) pp. 307–310.
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The pharyngeal teeth are hooked, and are in a 2, 4–4, 2 or 1, 4–4, 1 pattern. Shiners have a short and blunt snout, and the upper lip is separated from the skin of the snout by a deep groove that is continuous across the midline. The cartilaginous ridge of the lower jaw is not very evident.Bailey, R.M., and M.O. Allum. 1962.
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Myliobatidae are free-swimming rays whose pectoral fins make up broad, powerful "wings" which include the eagle and cow-nose rays. They feed on molluscs and have dentitions adapted to crushing. Dentitions of durophagous myliobatids show several specializations in the jaws and teeth related to their diet. The cartilaginous jaws are strengthened by calcified struts (trabeculae), and the palatoquadrate and mandibular symphysis are fused.
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The primitive skeleton is cartilage, a solid avascular (without blood vessels) tissue in which individual cartilage-matrix secreting cells, or chondrocytes, occur. Chondrocytes do not have intercellular connections and are not coordinated in units. Cartilage is composed of a network of collagen type II held in tension by water-absorbing proteins, hydrophilic proteoglycans. This is the adult skeleton in cartilaginous fishes such as sharks.
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Belantsea (named after a legendary ancestor of the Crow Nation) is a genus of extinct petalodontid cartilaginous fish that lived during the Lower Carboniferous, about 350 million years ago. Its fossils are found in the Bear Gulch Limestone lagerstätte. Its body was leaf-shaped, with muscular fins and a small tail. Such a body plan would allow for great maneuverability, but at the cost of speedy cruising.
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They are assumed to have had a cartilaginous housing of the ear mechanism. Nimravid feet were short, indicating they walked in a plantigrade or semiplantigrade posture. Although some nimravids physically resembled the sabre-toothed cats of the genus Smilodon, they were not closely related, but evolved a similar form through parallel evolution. They possessed synapomorphies with the barbourofelids in the cranium, mandible, dentition, and postcranium.
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Their bodies tend to be dorso-ventrally flattened, and they usually have five pairs of gill slits and a large mouth set on the underside of the head. The dermis is covered with separate dermal placoid scales. They have a cloaca into which the urinary and genital passages open, but not a swim bladder. Cartilaginous fish produce a small number of large yolky eggs.
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There are cartilaginous plates inside the mouth and the central, lingual plate has nine to thirteen teeth, a fact that distinguishes it from other lamprey species. The single nostril is between the eyes and seven naked gill pores are behind them. The only fins are two dorsal fins that run most of the way along the spine, and a small diamond- shaped tail fin.
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Another isotype, shark IgW, is related to mammalian IgD. TCRs, both α/β and γ/δ, are found in all animals from gnathostomes to mammals. The organization of gene segments that undergo gene rearrangement differs in cartilaginous fishes, which have a cluster form as compared to the translocon form in bony fish to mammals. Like TCR and Ig, the MHC is found only in jawed vertebrates.
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Horizontal translational movement is about 3.0 mm, vertical gliding about 2.5 mm with great movement horizontally than vertically. The gliding movements are smaller in males than in females . Type B is in 24% of females and 20% of males. In contrary to type A it lacks a definite "facet" and the two cartilaginous parts of the articulation are joined only by soft connective tissue.
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The smooth butterfly ray (Gymnura micrura) is a species of cartilaginous fish in the family Gymnuridae. It is a member of the order Myliobatiformes, which contains 10 total families. Its natural habitats are shallow seas, subtidal aquatic beds, estuarine waters, and coastal saline lagoons. Its common name is derived from its compressed body, pectoral fins that are wider than their length, and overall diamond shape.
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The octopus central brain contains 40 to 45 million cells. The brain-to-body mass ratio of the octopus is the highest of all the invertebrates and larger than that of most fish and reptiles (i.e. vertebrates). However, scientists have noted that brain size is not necessarily related to the complexity of its function. Octopuses have centralized brains located inside a cartilaginous capsule surrounding the oesophagus.
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While some small teeth have been found, few fossilized skeletons of manta rays have been discovered. Their cartilaginous skeletons do not preserve well, as they lack the calcification of the bony fish. Only three sedimentary beds bearing manta ray fossils are known, one from the Oligocene in South Carolina and two from the Miocene and Pliocene in North Carolina. Click on "Age range and collections".
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Previously, it was considered a redundant, evolutionary remnant, but is now considered integral to shoulder stability. Most agree that the proximal tendon of the long head of the biceps brachii muscle becomes fibrocartilaginous prior to attaching to the superior aspect of the glenoid. The long head of the triceps brachii inserts inferiorly, similarly. Together, all of those cartilaginous extensions are termed the 'glenoid labrum'.
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The phyllodes have a length of and a diameter and have thin longitudinal nerves with short soft hairs in between. The simple inflorescences mostly occur singly in the axils as cylindrical flower-spikes with a length of . Following flowering brown and straight seed pods with an oblong shape form. The pods have a length of and a width of and are cartilaginous with longitudinal reticulated nerves.
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The leaves are evenly distributed along the stem. The firm, blue-green leaf blades are up to 10 centimeters long by 1 centimeter wide, and are lance-shaped, widest distal to the bases. The leaf blade margins are cartilaginous, becoming white in color when dry. The plant has open flowers on the stem inflorescence and cleistogamous, unopening flowers which grow underground on white, self- pollinating spikelets.
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Aetobatus laticeps, the Pacific white-spotted eagle ray, is a species of cartilaginous fish in the eagle ray family Myliobatidae. It is found in the tropical East Pacific Ocean, ranging from Baja California to northern Peru, including the Galápagos.Gill, T.N. (1865) Note on the family of myliobatoids, and on a new species of Aetobatis. Annals of the Lycium of Natural History of New York 8: 135–138.
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The skin is naked and covers the body like a loosely fitting sock. They have cartilaginous skulls (although the part surrounding the brain is composed primarily of a fibrous sheath) and tooth-like structures composed of keratin. Colors depend on the species, ranging from pink to blue-grey, and black or white spots may be present. Eyes are simple eyespots, not lensed eyes that can resolve images.
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They use their hands to shove food in their mouths and down their throats and a hyobranchial pump to draw or suck things in their mouth. Pipidae have powerful legs for swimming and lunging after food. They also use the claws on their feet to tear pieces of large food. They have no external eardrums, but instead subcutaneous cartilaginous disks that serve the same function.
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Some of the outer parts of the scapula are cartilaginous at birth, and would therefore undergo endochondral ossification. At birth, a large part of the scapula is osseous, but the glenoid cavity, the coracoid process, the acromion, the vertebral border and the inferior angle are cartilaginous. From the 15th to the 18th month after birth, ossification takes place in the middle of the coracoid process, which as a rule becomes joined with the rest of the bone about the 15th year. Between the 14th and 20th years, the remaining parts ossify in quick succession, and usually in the following order: first, in the root of the coracoid process, in the form of a broad scale; secondly, near the base of the acromion; thirdly, in the inferior angle and contiguous part of the vertebral border; fourthly, near the outer end of the acromion; fifthly, in the vertebral border.
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The Devonian period is traditionally known as the "Age of Fish", marking the diversification of numerous extinct and modern major fish groups.. Among them were the early bony fishes, who diversified and spread in freshwater and brackish environments at the beginning of the period. The early types resembled their cartilaginous ancestors in many features of their anatomy, including a shark-like tailfin, spiral gut, large pectoral fins stiffened in front by skeletal elements and a largely unossified axial skeleton. They did, however, have certain traits separating them from cartilaginous fishes, traits that would become pivotal in the evolution of terrestrial forms. With the exception of a pair of spiracles, the gills did not open singly to the exterior as they do in sharks; rather, they were encased in a gill chamber stiffened by membrane bones and covered by a bony operculum, with a single opening to the exterior.
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The petrosquamous suture is a cranial suture between the petrous portion and the squama of the temporal bone. It forms the Koerner's septum. The petrous portion forms the medial component of the osseous margin, while the squama forms the lateral component. The anterolateral portion (squama) arises from the mesenchyme at 8 weeks of embryogenesis while the petromastoid portion develops later from a cartilaginous center at 6 months of fetal development.
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Several bones and cartilages make up the bony-cartilaginous framework of the nose, and the internal structure. The nose is also made up of types of soft tissue such as skin, epithelia, mucous membrane, muscles, nerves, and blood vessels. In the skin there are sebaceous glands, and in the mucous membrane there are nasal glands. The bones and cartilages provide strong protection for the internal structures of the nose.
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The finless sleeper ray (Temera hardwickii) is a species of electric ray in the family Narkidae, and the sole member of its genus. It is found over the continental shelf of Southeast Asia from the eastern Andaman Sea to Vietnam and Borneo. Typically growing no more than long, it may be the smallest cartilaginous fish. The finless sleeper ray is the only electric ray that lacks dorsal fins.
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The tail terminates in a fairly large, triangular caudal fin about as long as wide, with rounded corners. The skin entirely lacks dermal denticles. This species is plain light brown dorsally, sometimes with darker markings and whitish spots, and pale ventrally, with broad darker margins on the pectoral and pelvic fins. Possibly the smallest cartilaginous fish, the smallest known adult finless sleeper ray measured only long and weighed .
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It has a long, broad snout with prominent nasal skin flaps, and tall, triangular upper teeth. Its pectoral fins are long and almost straight, and there is a ridge on its back between the two dorsal fins. Hunting close to the sea floor, the bignose shark feeds on bony and cartilaginous fishes, and cephalopods. It is viviparous, meaning the embryos are sustained to term via a placental connection.
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Its ribcage was not strengthened by ossified uncinate processes but cartilaginous processes were likely present. The Las Hoyas Unit 3 site was once a forest surrounding a lake; the climate was warm with a distinct dry season. Since the skull is not known, the diet of Iberomesornis remains a subject of guesswork. It perhaps hunted insects and other small animals, plucking them out of the air or from the ground.
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Members of the mollusc family use intracellular digestion to function. Most molluscs have muscular mouths with radulae, "tongues", bearing many rows of chitinous teeth, which are replaced from the rear as they wear out. The radula primarily functions to scrape bacteria and algae off rocks, and is associated with the odontophore, a cartilaginous supporting organ. The radula is unique to the molluscs and has no equivalent in any other animal.
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Chimaera monstrosa, also known as the rabbit fish or rat fish, is a northeast Atlantic and Mediterranean species of cartilaginous fish in the family Chimaeridae. The rabbit fish is known for its characteristically large head and small, tapering body. With large eyes, nostrils, and tooth plates, the head gives them a rabbit-like appearance, hence the nickname “Rabbit fish”. They can grow to and live for up to 30 years.
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Convenience polyandry occurs when females mate with multiple males to avoid to coercive breeding harassment from these males. This type of polyandry was found throughout a variety of elasmobranch fish, or cartilaginous fish, such as sharks.Veríssimo, A., Grubbs, D., McDowell, J., Musick, J. & Portnoy, D. Frequency of multiple paternity in the spiny dogfish Squalus acanthias in the western north Atlantic. The Journal of heredity 102, 88–93 (2011).
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This brown alga is loosely secured to the rock by the felted rhizoids on the underside. Young individuals are circular and have a smooth surface and a double fringe of short hairs round the margin. Older individuals may be up to across and be fan-shaped or have broad blades with irregular margins. The consistency of the thallus is cartilaginous or leathery, and the colour is yellowish-brown or olive brown.
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Echidnas have tiny mouths and toothless jaws. The echidna feeds by tearing open soft logs, anthills and the like, and using its long, sticky tongue, which protrudes from its snout, to collect prey. The ears are slits on the sides of their heads that are usually unseen, as they are blanketed by their spines. The external ear is created by a large cartilaginous funnel, deep in the muscle.
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Annulicorona is an extinct genus of cartilaginous fish from Upper Triassic epoch of the Triassic period. Its name comes from the Latin Annulis meaning ring and Corona meaning crown, referring to the ring around the base of the crown of dermal denticles. It is known from the isolated dermal denticles of a single species, A. pyramidalis. The name refers to the roughly pyramid-shaped crown of the referred dermal denticles.
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Thompson described Hitler in the following terms: "He is formless, almost faceless, a man whose countenance is a caricature, a man whose framework seems cartilaginous, without bones. He is inconsequent and voluble, ill poised and insecure. He is the very prototype of the little man." Later, when the full force of Nazism had crashed over Europe, Thompson was asked to defend her "Little Man" remarks; it seemed she had underestimated Hitler.
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The texture of the leaves may be cartilaginous, leathery or herbaceous. The flowers are at the end of one or several branching inflorescence stalks, that carry several bracts much smaller than the leaves, at least substending each of the branches. These inflorescence stalks may be roughly hairy to hairless, and round or angular in cross-section. The compounded inflorescences may be compact or loosely composed racemes, panicles or corymbs.
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As a result of the constant digging action, elements of the forelimb that are associated with those movements will begin to ossify. Some elements in the hands of Talpa europaea, formally described as distal phalanges, are actually the first to ossify. These elements build up a groove for the distal phalanges, but ultimately do not fuse with them. These bony elements develop directly, meaning they do not have any cartilaginous precursors.
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In cartilaginous fishes, the part of the archinephric duct closest to the testis is coiled up to form an epididymis. Below this are a number of small glands secreting components of the seminal fluid. The final portion of the duct also receives ducts from the kidneys in most species. In amniotes, however, the archinephric duct has become a true vas deferens, and is used only for conducting sperm, never urine.
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Size comparison The respiratory tube is also known in LACM 128319, preserved as cartilaginous tracheal rings. Only the posterior- most end of the tracheal tube – at the end of the neck near the pectoral girdle – is known. The section where the two bronchi split was also preserved in the specimen, but was destroyed during excavation. This is an indication that Platecarpus and other mosasaurs had two functional lungs.
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Giles uses x-ray tomography to study the bone structure of Actinopterygii. Whilst the long-held assumption was that sharks were primitive forms of fish, Giles found that our latest common ancestors are not like sharks, but common bony and cartilaginous. Giles identified a new genus of Actinopterygii, which provided a new model of cranial anatomy. She used synchrotron-CT scans to examine the endoskeletal anatomy of Cheirolepis.
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Distinctively, these fish have no jaws. Cartilaginous fish, such as sharks, also have simple skulls. The cranium is a single structure forming a case around the brain, enclosing the lower surface and the sides, but always at least partially open at the top as a large fontanelle. The most anterior part of the cranium includes a forward plate of cartilage, the rostrum, and capsules to enclose the olfactory organs.
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The well-preserved forelimbs are the most distinctive parts of A. simonsi. A broad scapula and a ball-and-socket shoulder joint is characteristic of cetaceans, but Ancalecetus lacks both. The interior surface of the narrow scapula is not broadly curved as in most cetaceans, but tightly curved. The roughened vertebral border suggests the presence of a cartilaginous extension that extends the surface of the scapula like in modern cetaceans.
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This list of fossil fishes described in 2016 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes and other fishes of every kind that have been described during the year 2016, as well as other significant discoveries and events related to paleontology of fishes that occurred in the year 2016. The list only includes taxa at the level of genus or species.
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Normally, the septum lies centrally, and thus the nasal passages are symmetrical. A deviated septum is an abnormal condition in which the top of the cartilaginous ridge leans to the left or the right, causing obstruction of the affected nasal passage. The condition can result in poor drainage of the sinuses. People can also complain of difficulty breathing, headaches, bloody noses, or of sleeping disorders such as snoring or sleep apnea.
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The stem is long, thick, equal in width throughout, and with a cartilaginous texture. It is hollow, not hairy, either smooth or twisted with longitudinal striations, often with a long pseudorrhiza (a subterranean elongation of the stem) at the base. The stem color is pale grayish white on the upper portion, and pale grayish black below; the base becomes somewhat dirty brown in age, but does not develop reddish stains.
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Both sexes mature at around six years of age, and can live to at least 11 years. The crossback stingaree may hybridize naturally with the closely related yellowback stingaree off southern New South Wales, where the distributions of the two species overlap and apparent hybrid offspring with intermediate color patterns have been found. If true, this would represent one of the few known cases of hybridization among cartilaginous fishes.
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Crustospathula was circumscribed by lichenologist André Aptroot in 1998, with Crustospathula cartilaginea as the type species. This species was discovered by Aptroot in Madang Province, Papua New Guinea in an undisturbed tropical lowland rain forest. It was, according to Aptroot, the known instance of a crustose lichen with stalked, cartilaginous, labriform soralia. For this reason, it could not be assigned to any known genera, and Crustospathula was created to hold it.
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Neither of these traits are common in amniotes. The braincase had a mosaic of features in common with various tetrapodomorphs. The system of grooves and nerve openings on the side of the braincase were unusually similar to those of the fish Megalichthys, and the cartilaginous base is another plesiomorphic feature. However, the internal carotid arteries perforate the braincase near the rear of the bone complex, a derived feature similar to amniotes.
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The clearnose skate (Raja eglanteria) is species of cartilaginous fish in the family Rajidae. R. eglanteria is also known by other common names such as the brier skate and summer skate. Clearnose skates are easily identified by the translucent patches on either side of their snouts and their mottled dorsal surface. They are found along the Atlantic and Gulf coasts of the United States in shallow waters of the continental shelf.
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However, in many analyses, this definition would be synonymous with the more widely used name Ornithurae. An alternate definition was provided in 2001, naming Carinatae an apomorphy-based clade defined by the presence of a keeled sternum. The most primitive known bird relative with a keeled breastbone is Confuciusornis. While some specimens of this stem-bird have flat breastbones, some show a small ridge that could have supported a cartilaginous keel.
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Development, 105(4), 787-794. and is present widely across the evolutionary diversity of bilaterian animals, although it has been lost in evolution in arthropods and nematodes. Despite the gene name being Pdx1, there is no Pdx2 gene in most animals; single-copy Pdx1 orthologs have been identified in all mammals. Coelacanth and cartilaginous fish are, so far, the only vertebrates shown to have two Pdx genes, Pdx1 and Pdx2.
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They resemble primitive bone marrow in hagfish. Cartilaginous fish (sharks and rays) have a more advanced immune system. They have three specialized organs that are unique to chondrichthyes; the epigonal organs (lymphoid tissues similar to mammalian bone) that surround the gonads, the Leydig's organ within the walls of their esophagus, and a spiral valve in their intestine. These organs house typical immune cells (granulocytes, lymphocytes and plasma cells).
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These cusps are also attached via chordae tendinae to two papillary muscles projecting from the ventricular wall. The papillary muscles extend from the walls of the heart to valves by cartilaginous connections called chordae tendinae. These muscles prevent the valves from falling too far back when they close. During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight.
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This would have given the animal an appearance similar to modern bats, in an example of convergent evolution. However, in bats, the membrane stretches between the fingers only, no styliform wrist bone being present. Ossified styliform bones are found, however, in the wings of some modern gliding animals like flying squirrels. The greater glider, and the prehistoric gliding rodent Eomys quercyi, also have a similarly long cartilaginous styliform element.
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The epiglottis is present in mammals, including land mammals and cetaceans, also as a cartilaginous structure. Like in humans, it functions to prevent entry of food into the trachea during swallowing. The position of the larynx is flat in mice and other rodents, including rabbits. For this reason, because the epiglottis is located behind the soft palate in rabbits, they are obligate nose breathers, as are mice and other rodents.
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The family Torpedinidae contains 22 species of electric rays or torpedoes, flat cartilaginous fishes that produce electricity as a defense and feeding mechanism. They are slow-moving bottom-dwellers. The largest species is the Atlantic torpedo, Tetronarce nobiliana, which can grow to a weight of and deliver a 220-volt electric shock. Electric rays have patches of modified muscle cells called electroplaques that make up an electric organ.
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One group of temnospondyls, the Branchiosauridae, is also known from larval specimens. Branchiosaurids like Branchiosaurus and Apateon are represented by many fossils preserving skin and external gills. An entire growth series is exhibited in the wide range of sizes among specimens, but the lack of terrestrially adapted adult forms suggests that these temnospondyls were neotenic. Unlike other temnospondyls, their postcranial skeletons developed quickly but were still partly cartilaginous when fully mature.
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This list of fossil fishes described in 2015 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes and other fishes of every kind that have been described during the year 2015, as well as other significant discoveries and events related to paleontology of fishes that occurred in the year 2015. The list only includes taxa at the level of genus or species.
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In embryogenesis, the skeletal system is derived from the mesoderm germ layer. Chondrification (also known as chondrogenesis) is the process by which cartilage is formed from condensed mesenchyme tissue, which differentiates into chondrocytes and begins secreting the molecules that form the extracellular matrix. Early in fetal development, the greater part of the skeleton is cartilaginous. This temporary cartilage is gradually replaced by bone (Endochondral ossification), a process that ends at puberty.
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The blind electric rays are small, flat cartilaginous fish with the round pectoral fin disc characteristic of electric rays, a short, fleshy tail, and one dorsal fin. The front part of their pelvic fins are modified for walking, while the back is fused to the disk. Their eyes are not visible externally and are practically useless, hence the name. The coloration is dark brown above and lighter below.
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Narcinidae, or numbfishes, are a family of electric rays (order Torpediniformes). They are bottom-dwelling cartilaginous fishes with large, rounded pectoral fin discs and long tails. They can produce an electric discharge for defense, from which their scientific name is derived (Greek narke, meaning "paralysis"). Members of this family are commonly known as the numbfishes, and are found almost worldwide in warm temperate and tropical continental and continental insular waters.
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Voracious and opportunistic in feeding habits, the blotchy swellshark is known to consume numerous types of fishes and invertebrates, including an unusually high diversity of cartilaginous fishes. Like other Cephaloscyllium species, it is capable of rapidly inflating its body as a defense against predators. This species is oviparous, with females laying encapsulated eggs two at a time. There is no well-defined breeding season and reproduction occurs year-round.
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Figure 4 Ossification 180px Figure 6 Peculiarities 180px The sternum develops from two cartilaginous bars one on the left and one on the right, connected with the cartilages of the ribs on each side. These two bars fuse together along the middle to form the cartilaginous sternum which is ossified from six centers: one for the manubrium, four for the body, and one for the xiphoid process. The ossification centers appear in the intervals between the articular depressions for the costal cartilages, in the following order: in the manubrium and first piece of the body, during the sixth month of fetal life; in the second and third pieces of the body, during the seventh month of fetal life; in its fourth piece, during the first year after birth; and in the xiphoid process, between the fifth and eighteenth years. The centers make their appearance at the upper parts of the segments, and proceed gradually downward.
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The Graeco–Latin nomenclature of the frilled shark derives from the Greek chlamy (frill) and selachus (shark), and the Latin anguineus (like an eel); besides its common name, the frilled shark also is known as the "lizard shark" and as the "scaffold shark". In the article "An Extraordinary Shark", the zoologist Samuel Garman depicts a frilled shark (Clamydoselachus anguineus); the superior inset depicts dorsal and ventral views of the shark's head; the inferior inset depicts two, trident-shaped teeth. (Bulletin of the Essex Institute, vol. XVI, 1884) Initially, marine scientists considered the frilled shark a living, evolutionary representative of the extinct elasmobranchii subclass of cartilaginous fish (rays, sharks, skates, sawfish); because the shark's body featured primitive anatomic traits, such as long jaws with trident-shaped, multi-cusp teeth; amphistyly, the direct articulation of the jaws to the cranium, at a point behind the eyes; and a quasi-cartilaginous notochord (a proto-spinal-column) composed of indistinct vertebrae.
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This list of fossil fishes described in 2017 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes and other fishes of every kind that are scheduled to be described during the year 2017, as well as other significant discoveries and events related to paleontology of fishes that are scheduled to occur in the year 2017. The list only includes taxa at the level of genus or species.
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In the cartilaginous part of the baculum, the central digit is smaller than those at the sides.Weksler, 2006, pp. 55–56 In Drymoreomys, there are three digits at the tip of the penis, of which the central one is the largest. In Thomasomys ucucha the glans penis is rounded, short, and small and is superficially divided into left and right halves by a trough at the top and a ridge at the bottom.
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One of these radioles, called an operculum, is a highly specialized structure located on the dorsal part of the head. The operculum consists of a long, thick stalk with a cartilaginous, cone-shaped plug at the distal end. This plug can be used to seal the opening of the tube after the animal has retreated inside. The operculum, which is usually red in color, secretes a mucus which seems to possess antibiotic properties.
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The five sacral vertebrae have not yet fused into a real sacrum. The tail vertebrae are platycoelous with low spines and backward slanting chevrons. There are at least twelve pairs of dorsal ribs; some displaced elements might represent a thirteenth pair. The third and fourth rib have expanded lower ends that in life probably were attached to cartilaginous sternal ribs, themselves connected to sterna that in the holotype specimen have not (yet) ossified.
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They are broad anteriorly (4–7 mm), white or whitish, in age flushed with pink, often with sordid-brownish stains, and with edges pallid and even. The stem is long, thick, very brittle and cartilaginous, equal, and tubular. It sometimes has a well-developed pseudorrhiza that resembles white cotton, and the base is covered with stiff white hairs, and often it stains reddish brown. The surface has fine straight or sometimes twisted longitudinal striations.
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The function of IgD has been a puzzle in immunology since its discovery in 1964. IgD is present in species from cartilaginous fish to human (with the possible exception of birds). This nearly ubiquitous appearance in species with an adaptive immune system demonstrates that IgD may be as ancient as IgM and suggests that IgD has important immunological functions. In B cells, the function of IgD is to signal the B cells to be activated.
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Cartilaginous fishes (sharks and rays) are covered with placoid scales. Some species are covered instead by scutes, and others have no outer covering on part or all of the skin. Fish scales are part of the fish's integumentary system, and are produced from the mesoderm layer of the dermis, which distinguishes them from reptile scales. The same genes involved in tooth and hair development in mammals are also involved in scale development.
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The placoid scales of cartilaginous fishes are also called dermal denticles and are structurally homologous with vertebrate teeth. It has been suggested that the scales of bony fishes are similar in structure to teeth, but they probably originate from different tissue. Most fish are also covered in a layer of mucus or slime which can protect against pathogens such as bacteria, fungi, and viruses, and reduce surface resistance when the fish swims.
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The basilar part of the occipital bone (also basioccipital) extends forward and upward from the foramen magnum, and presents in front an area more or less quadrilateral in outline. In the young skull this area is rough and uneven, and is joined to the body of the sphenoid by a plate of cartilage. By the twenty-fifth year this cartilaginous plate is ossified, and the occipital and sphenoid form a continuous bone.
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Partial bones of crocodiles were discovered. Of the seabirds, fragmentary bones of cormorants and petrels were discovered, as well as two species of boobies. The remains of many cartilaginous fish were discovered in this formation, including more than 3,500 shark teeth, which mainly belonged to the ground sharks, such as requiem sharks and hammerhead sharks. To a lesser extent, mackerel sharks were also found, such as white sharks, sand sharks, and Otodontidae.
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The disk-winged bat seeks a bud of rolled-up leaves with the opening at the top. It clings head-up to the smooth inner (ventral) surfaces of the leaves. Plants with this leaf morphology include Heliconia and Calathea species. This manner of roosting is said to facilitate rapid escape in the event of a potential disturbance. The bat’s disks take the shape of concave cups, and are supported by an internal cartilaginous plate.
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The specialized pharyngeal denticles with brush-like branches of Branchiosauridae are indicative of gill clefts and suggest a filter-feeding mechanism focusing on plankton. In well preserved specimens of Branchiosaurus, six rows of tooth-bearing ossicles are present on each side of the hyobranchial skeleton in a 1-2-2-1 configuration. This is consistent with the denticles being attached to the epithelium surrounding four cartilaginous ceratobranchials bordering three external gill- slits.Milner, A.R. 1982.
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These immature bone matrices are found in the epiphyseal plate at both the lower hypertrophic zone and the longitudinal septa of the cartilaginous matrix. One study was conducted on fetal cartilage discovered that the chondrocalcin protein exists as a dimer with 35,000 g/mol subunits. The reason why fetal cartilage was used is because chondrocalcin cannot be detected in mature bone. Another investigation was conducted to determine the mechanism behind calcium binding in chondrocalcin.
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William Charles Schroeder (1895–1977) was an American ichthyologist. He was born on Staten Island, New York. He, along with his lifelong colleague Henry Bryant Bigelow, made substantial contributions to the knowledge of the fish fauna of the western North Atlantic. The two described 42 new species of jawless fishes and cartilaginous fishes, and authored several seminal publications, including Fishes of the Western North Atlantic and Fishes of the Gulf of Maine.
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Normally, the cartilaginous notochord develops into the bony vertebrae in a human body. The COL2A1 gene results in malformed type II collagen, which is essential in the transition from collagen to bone. This is the first time that researchers found a persistent notochord in a human body due to a COL2A1 mutation.Codsi, Elisabeth et al. “Persistent Notochord in a Fetus with COL2A1 Mutation.” Case Reports in Obstetrics and Gynecology 2015 (2015): 935204. PMC. Web.
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The ribs form antero-ventral and postero-dorsal flanges, which are for the muscle attachments. Orthosuchus has similar pectoral girdles and pelvic girdles compare to living crocodiles, with a long scapula and a shorter coracoid. The interclavicle is hypothesized to be cartilaginous. As for the forelimb, the fossil records showed that Orthosuchus has similar humerus, but the distal and proximal expansions does not lay on the same plane as the modern crocodiles.
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Bony fishes, class Osteichthyes, are characterised by bony skeleton rather than cartilage. They appeared in the late Silurian, about 419 million years ago. The recent discovery of Entelognathus strongly suggests that bony fishes (and possibly cartilaginous fishes, via acanthodians) evolved from early placoderms. A subclass of the Osteichthyes, the ray-finned fishes (Actinopterygii), have become the dominant group of fishes in the post- Paleozoic and modern world, with some 30,000 living species.
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In France it is sold as "small salmon" (saumonette) and in Belgium and Germany it is sold as "sea eel" (zeepaling and Seeaal, respectively). It is also used as fertilizer, liver oil, and pet food. Because of its availability, cartilaginous skull, and manageable size, it is a popular vertebrate dissection specimen in both high schools and universities. Reported catches in 2000–2009 varied between 13,800 tonnes (in 2008) and 31,700 tonnes (in 2000).
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The eagle rays are a group of cartilaginous fishes in the family Myliobatidae, consisting mostly of large species living in the open ocean rather than on the sea bottom. Eagle rays feed on mollusks and crustaceans, crushing their shells with their flattened teeth. They are excellent swimmers and are able to breach the water up to several metres above the surface. Compared with other rays, they have long tails, and well-defined, rhomboidal bodies.
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The Izak catshark is harmless and of no commercial value. It is regularly caught incidentally (and discarded) by a bottom trawl fishery targeting hake south of Cape Town. In contrast to most cartilaginous fishes, its numbers have been increasing in the presence of commercial fishing. The reasons for this may include its high reproductive rate, its breeding in less-fished shallower waters, its hardiness allowing for high post-capture survival, and its opportunistic diet.
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In cartilaginous fish, this duct actually opens onto the top of the head, and in some teleosts, it is simply blind-ending. In all other species, however, it ends in an endolymphatic sac. In many reptiles, fish, and amphibians this sac may reach considerable size. In amphibians the sacs from either side may fuse into a single structure, which often extends down the length of the body, parallel with the spinal canal.
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Shortnose sturgeon are cartilaginous with bones only in the skull, jaw and pectoral girdle. It is a physostome fish, so its swim bladder is connected to the intestinal tract by a special duct. This duct allows for gas pressure regulation through swallowing air or releasing air through the gut. The intestines for shortnose sturgeon are dark and have a spiral valve (important for nutrient absorption), similar to that of sharks and rays.
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The gene is confined within Animals, as confident orthologs in fungi and chaonoflagettes were not found. The human gene shares defined homology with placental mammals, marsupials, monotremes, reptiles, birds, amphibians, cartilaginous fish and some homology in insects, lobe finned fish, chelicerates and corals (Figure 22). The following significant taxonomic groups do not yield confident homology: nematodes, cnidaria, platyhelminths, porifera, annelids, ctenophora, mollusca, echinodermata, myriapoda, agnatha, tunicata. Crustacea is a borderline case that may yield homology.
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The septum or nasal septum is the cartilaginous wall that divides the two nostrils. The cartilage is, however, usually not pierced. It is the thin strip of very soft and flexible skin, just between the cartilage and the bottom of the nose, where septum piercing is mostly done. Piercing the skin instead of the cartilage can greatly minimize the pain, as well as other discomforts associated with this type of body piercing.
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Finally, plasma analysis will demonstrate elevated uroporphyrin and coproporphyrin. Other nonspecific but helpful diagnostic clues are history of cutaneous photosensitivity, blistering, erosions, crusts and ulcerations leading to extensive scarring and deformation of the hands, loss of eyebrows, eyelashes with severe mutilation of cartilaginous structures like the nose, erythrodontia, and variable degree of hematologic involvement ranging from mild hemolytic anemia to intrauterine hydrops fetalis. Other early clues are red or violet staining of diapers.
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The remaining leg pairs have a weak claw at the tip. Lost legs or the telson (tail) may slowly regenerate, and cracks in the body shell can heal. Behind its legs, the horseshoe crab has book gills, which exchange respiratory gases, and are also occasionally used for swimming. As in other arthropods, a true endoskeleton is absent, but the body does have an endoskeletal structure made up of cartilaginous plates that support the book gills.
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Timing of gene expression during development varies from tissue to tissue. Basement membranes are often the driving force behind separating epithelia from stroma and connective tissue. Perlecan is of particular importance in cardiovascular, neural and cartilaginous development. Pre-implantation blastocyst development is a controlled cascade of gene regulation and intercellular signaling. Extracellular perlecan has been observed at the blastocyst stage of mouse embryonic development, specifically upregulated at the point when the embryo reaches “attachment competence”.
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Below the shell gland is the ovisac, a distended region in which eggs are stored prior to laying. In ovoviviparous species, the egg remains within the ovisac until it hatches. Some cartilaginous fishes, however, are truly viviparous, giving birth to live young, and producing no egg shell. In these forms, the ovisac nurtures the developing embryo, often with the aid of vascular outgrowths similar to, but much simpler than, the mammalian placenta.
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In such cases, species have diverged in terms of body size and dentition, apparently facilitating niche differentiation. The members of this genus are characterized by a small body — some species are less than in snout–vent length (tail roughly doubles the total body length). Their extreme miniaturization is accompanied by determinate growth and skeletal reduction. Their skeleton also shows unique features, such as ossifications of many elements that remain cartilaginous in other salamanders.
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Insertion of the tensor tympani muscle onto the malleus. . AA’ ( two fibrous collagenic layers); B épidermis; C mucous membrane; D head of malleus; E incus; F stapes; G tensor tympani; H lateral process of malleus; I Manubrium of malleus; J stapedius muscle. The tensor tympani is a muscle that is present in the middle ear. It arises from the cartilaginous part of the auditory tube, and the adjacent great wing of the sphenoid.
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Fish head parts, 1889, Fauna of British India, Sir Francis Day Skull of a swordfish The skull of fishes is formed from a series of only loosely connected bones. Lampreys and sharks only possess a cartilaginous endocranium, with both the upper and lower jaws being separate elements. Bony fishes have additional dermal bone, forming a more or less coherent skull roof in lungfish and holost fish. The lower jaw defines a chin.
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The limestone laid down around Alpena comes from the Devonian Period, the 4th period of the Paleozoic Era (roughly 416-358 million years ago) the "Age of the Fishes". Marine life was intensely diverse, before formation of the supercontinent of Pangaea, when 85% of the earth's surface was oceans. Fish of this period were cartilaginous, mainly shark ancestors. Cartilage does not fossilize, so fossils from the area are typically be from "filter feeding" creatures.
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Often, the sympatric overlap in characteristics between these species makes it difficult to identify a specific species. The most distinguishing feature of the white- ankled mouse, and the one most used to identify the species, is the baculum of males (Hooper 1958). The tip of the white-ankled mouse’s baculum is long and cartilaginous, whereas the tip of the Brush and Texas mice is short and rounded (Clark 1952 and Hooper 1958).
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The thallus of this species is dark red in colour and tough in texture, it grows to 30 cm long and 1 cm wide. It is perennial and attached by a discoid holdfast, it grows in tufts, erect, firm and cartilaginous. All the axes and branches are compressed or flat with an inconspicuous central midrib. The lateral branches are short and are produced alternately from near the base, they are deeply toothed.
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This was found from the morphology of the Holostei, for example presence of a paired vomer. Holosteans are closer to teleosts than are the chondrosteans, the other group intermediate between teleosts and cartilaginous fish, which are regarded as (at the nearest) a sister group to the Neopterigii. The spiracles are reduced to vestigial remnants and the bones are lightly ossified. The thick ganoid scales of the gars are more primitive than those of the bowfin.
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One Continuoolithus egg contains embryonic remains representing a relatively early stage of development so that the skeleton was almost entirely cartilaginous, which has been largely replaced in the fossil by an amorphous calcite mass. Two long skeletal elements are recognizable, however. Both of them appear to be in the very earliest stages of bone formation (ossification). The shorter of the two (measuring long) is thought to be a femur because of its shape.
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It grows from a discoid holdfast stipe, the fronds are channelled unlike those of Chondrus crispus which are flat. It grows to a height of 10 to 20 cm and branches dichotomously. The frond is cartilaginous and reddish-brown in colour, showing a greenish or purplish tinge. The mature algae show reproductive structures which develop on erect filaments up to 1 mm in diameter, these make it readily distinguishable from Chondrus crispus.
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The most common dinosaur in the paleoenvironment preserved in this formation is Tenontosaurus. Other vertebrates present at the time of Tenontosaurus included the amphibian Albanerpeton arthridion, the reptiles Atokasaurus metarsiodon and Ptilotodon wilsoni, the crurotarsan reptile Bernissartia, the cartilaginous fish Hybodus buderi and Lissodus anitae, the ray-finned fish Gyronchus dumblei, the crocodilian Goniopholis, and the turtles Glyptops and Naomichelys.Nydam, R.L. and R. L. Cifelli. 2002a. Lizards from the Lower Cretaceous (Aptian-Albian) Antlers and Cloverly formations.
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The spotted ratfish (Hydrolagus colliei) is a chimaera found in the north- eastern Pacific Ocean. Often seen by divers at night in the Pacific Northwest, this cartilaginous fish gets its characteristic name from a pointed rat-like tail. The ratfish lays leathery egg cases on the bottom of muddy or sandy areas, which are often mistaken by divers as something inanimate. While mainly a deep-water species, it occurs at shallower depths in the northern part of its range.
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Chimaeras are cartilaginous fish in the order Chimaeriformes, known informally as ghost sharks, rat fish, spookfish, or rabbit fish; the last three names are not to be confused with rattails, Opisthoproctidae, or Siganidae, respectively. At one time a "diverse and abundant" group (based on the fossil record), their closest living relatives are sharks and rays, though their last common ancestor with them lived nearly 400 million years ago. Today, they are largely confined to deep water.
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The simple inflorescences occur as cylindrical flower-spikes that are in length and are moderately densely packed with yellow flowers. After flowering cartilaginous brown-black seed pods form that have a linear with a length of around and a width of about . The pods are glaborus and straight with a powdery white coating and thick, yellowish marginal nerves and longitudinally arranged seeds inside. The pale brown seeds are in length and around wide with a yellow and folded funicle.
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There will be skin, cartilaginous structures, and cartilage (although the later is not seen in all variants of this disorder). Some investigators believe that the tragus is the only hillock which is derived from the first branchial arch. This is clearly suggestive that true cases of Accessory Auricle represent a true duplication of the hillocks that were part of the second branchial arch. The second ear appears as a mirror image folded forward and lying on the posterior cheek.
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It is tough and cartilaginous, and its base it covered with white hairs. Overall, its color is that of the cap or paler, and often paler near the top. The edibility of the mushroom is unknown. Spores are broadly ellipsoid in shape, amyloid, and have dimensions of either 8–10 by 6–7 µm or 10–14 by 6.7–8.5 µm depending on whether they originated from four-or two-spored basidia (spore- bearing cells), respectively.
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MOE follows a much more chronic and indolent course than ordinary acute otitis externa. There may be granulation involving the floor of the external ear canal, most often at the bony-cartilaginous junction. Paradoxically, the physical findings of MOE, at least in its early stages, are often much less dramatic than those of ordinary acute otitis externa. In later stages, there can be soft tissue swelling around the ear, even in the absence of significant canal swelling.
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Pathology of the affected bronchi by bronchoscopy showing the deficiency of cartilaginous plates in the bronchial wall is the confirmatory test. However, lung biopsy has several complications and is not always diagnostic. Considering its non-invasive methodology, facility of execution, and good patient tolerance, multi-slice spiral CT or CT bronchoscopy should be the test of choice to study cystic lung diseases in particular WCS. Radiologically, the lungs are overinflated, and on bronchoscopy bronchomalacia is demonstrated.
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Bathyraja panthera, the leopard skate, is a species of cartilaginous fish in the family Arhynchobatidae. It was first described as a new species in 2011, having been discovered in the Aleutian Islands at depths between . It is a moderately large species with a short snout and wide mouth. The dorsal surface is pale greenish-brown, with speckling, round black spots and yellow blotches, giving it its specific name panthera from its resemblance to a leopard skin.
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7], or of the vertical fissure which occasionally intersects this part of the bone constituting the malformation known as fissura sterni; these conditions are further explained by the manner in which the cartilaginous sternum is formed. More rarely still the upper end of the sternum may be divided by a fissure. Union of the various centers of the body begins about puberty, and proceeds from below upward [Fig. 5]; by the age of twenty-five they are all united.
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They have more blood volume per body mass and greater numbers of red cells per blood volume. Muscle myoglobin is up to twenty times more concentrated than in terrestrial mammals. Before diving, pinnipeds typically exhale to empty their lungs of half the air and then close their nostrils and throat cartilages to protect the trachea. Their unique lungs have airways that are highly reinforced with cartilaginous rings and smooth muscle, and alveoli that completely deflate during deeper dives.
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Features of both fore and hind flippers are unique and diagnostic of the species. Fur is absent on the top of the fore flippers and an abrupt "clean line" is seen across the wrist where the fur ends. The hind flippers are proportionately the longest in any otariid because of extremely long, cartilaginous extensions on all of the toes. Small claws are on digits 2–4, well back from the flap-like end of each digit.
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Its scales has evolved into small spines like other cartilaginous fish, Mola tecta has counter shading which means that it has a darker color on the dorsal side than the ventral side. Compared to other Mola species, Mola tecta is slimmer, has a sleeker adult body shape and lacks a protruding snout and lumps along the tail fin. It reaches up to three meters in length and weighing up to . Parasites are found in all the dissected Mola tecta.
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Hybrids are known between M. cucullatus and M. fimbriifolius from the Cape Peninsula on locations where both parents grow side by side. Intermediate in most characters, the general habitat is mostly like that of M. cucullatus, but the lowest part of the stems is stout, and the bark is thick and cartilaginous like that of M. fimbriifolius. A hybrid of M. capitulatus and M. hirtus was collected ones, and specimens made from cuttings have since been grown at Kirstenbosch.
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Quittor is an infection of the lower leg of equines, sometimes known as graveling. A condition once common in draft horses, it is characterized by inflammation of the cartilage of the lower leg. There are two forms, subcutaneous and cartilaginous. Quittor usually results from an injury to the leg, such as an abscess on the coronary band above the hoof, that allows foreign matter to get into the leg and then collect beneath the hoof, leading to an infection.
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Sclerorhynchidae is an extinct family of cartilaginous fish from the Cretaceous and Paleogene belonging to the order Rajiformes, which also contains extant skates. Despite their close appearance to extant sawfish (Pristidae), the two are not closely related, with sawfish being instead grouped with guitarfish in the order Rhinopristiformes. The genera Ischyrhiza, Onchopristis, and Schizorhiza were formerly considered members of this group, but evidence indicates that they form an unnamed sister group to Rajidae and are distinct from Sclerorhynchidae.
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A plate of clay was moulded to the side of the specimen where the ear would be anatomically. The outer edge of the ears were rounded and sloped down and slightly forward. Ear lobes are not presented in any of the specimens however there is a small peg of clay placed above the area where the ear attached to the head. This clay peg is postulated to represent the cartilaginous projection usually found in the a normal human ear.
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The two species of this genus can keep their blood temperature higher above that of the water surrounding them than other cartilaginous fish, with temperature differences recorded up to 15.6 °C.Abstract for S. D. Anderson, K. J. Goldman: “Temperature Measurements from Salmon Sharks, Lamna ditropis, in Alaskan Waters”, Copeia, Vol. 2001, No. 3, 2001-08-06C. Larsen, H. Malte, R. E. Weber: “ATP-induced Reverse Temperature Effect in Isohemoglobins from the Endothermic Porbeagle Shark”, Journal of Biological Chemistry vol.
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The main distinguishing feature of this group is the cartilaginous nature of the skeleton, although some older fish show a degree of calcification. The ancestors of the chondrosteans are thought to be bony fish, but that this characteristic of an ossified skeleton was lost in later evolutionary development, resulting in a lightening of the frame. Elderly chondrostean individuals show beginnings of ossification of the skeleton, which suggests this process is delayed rather than wholly lost in these fishes.
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Iniopterygiformes ("Nape Wing Forms") is an extinct order of chimaera-like cartilaginous fish that lived from the Devonian to Carboniferous periods (345–280 million years ago). Fossils of them have been found in Montana, Indiana, Illinois, and Nebraska. The Iniopterygians are characterized by large pectoral fins, wing-like projections on their backs, mounted high on the body and denticulated bony plates on the head and jaws. Iniopterygian sharks were small, and their average length was about .
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Adjacent slits are separated by a cartilaginous gill arch from which projects a long sheet-like septum, partly supported by a further piece of cartilage called the gill ray. The individual lamellae of the gills lie on either side of the septum. The base of the arch may also support gill rakers, small projecting elements that help to filter food from the water. A smaller opening, the spiracle, lies in the back of the first gill slit.
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Skulls of wild boar (left) and white-lipped peccary (right): Note how the upper canines of the peccary point downwards. A peccary is a medium-sized animal, with a strong resemblance to a pig. Like a pig, it has a snout ending in a cartilaginous disc, and eyes that are small relative to its head. Also like a pig, it uses only the middle two digits for walking, although, unlike pigs, the other toes may be altogether absent.
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They are similar in structure to those of a fish and are enclosed in a cartilaginous capsule fused to the cranium. The cornea is formed from a translucent epidermal layer and the slit-shaped pupil forms a hole in the iris and lies just behind. The lens is suspended behind the pupil and photoreceptive retinal cells cover the back of the eye. The pupil can be adjusted in size and a retinal pigment screens incident light in bright conditions.
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The limbs of the juvenile hadrosaurs are anatomically and proportionally similar to those of adult animals. However, the joints often show "predepositional erosion or concave articular surfaces", which was probably due to the cartilaginous cap covering the ends of the bones. The pelvis of a young hadrosaur was similar to that of an older individual. Evidence suggests that young hadrosaurs would have walked on only their two hind legs, while adults would have walked on all four.
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Forming the oral edge of the upper jaw in most jawed vertebrates, the premaxillary bones comprise only the central part in more primitive forms. They are fused in blowfishes and absent in cartilaginous fishes such as sturgeons. Reptiles and most non-mammalian therapsids have a large, paired, intramembranous bone behind the premaxilla called the septomaxilla. Because this bone is vestigial in Acristatherium (a Cretaceous eutherian) this species is believed to be the oldest known therian mammal.
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Skeleton of a bony fish There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body. The skeleton of the fish is made of either cartilage (cartilaginous fishes) or bone (bony fishes). The fins are made up of bony fin rays and, except for the caudal fin, have no direct connection with the spine. They are supported only by the muscles.
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The spleen is found in nearly all vertebrates. It is a non-vital organ, similar in structure to a large lymph node. It acts primarily as a blood filter, and plays important roles in regards to red blood cells and the immune system.Spleen, Internet Encyclopedia of Science In cartilaginous and bony fish it consists primarily of red pulp and is normally a somewhat elongated organ as it actually lies inside the serosal lining of the intestine.
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In amphibians, lampreys, and hagfish, the cerebellum is little developed; in the latter two groups, it is barely distinguishable from the brain-stem. Although the spinocerebellum is present in these groups, the primary structures are small paired nuclei corresponding to the vestibulocerebellum. The cerebellum of cartilaginous and bony fishes is extraordinarily large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei.
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The narrow sawfish (Anoxypristis cuspidata), also known as the pointed sawfish or knifetooth sawfish, is a species of sawfish in the family Pristidae, part of the Batoidea, a superorder of cartilaginous fish that include the rays and skates. Sawfish display a circumglobal distribution in warm marine and freshwater habitats. Their extant biodiversity is limited to five species belonging to two genera (Pristis and Anoxypristis). The sawfishes are characterised by the long, narrow, flattened rostrum or extension on their snout.
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Bones in both maxilla and mandible respond to their respective cartilaginous growth centers. To test this theory, two approaches were taken by researchers in past. Either the cartilage was removed from the nasal septum or the cartilage was transplanted into the cultures to see the effects on the growth. When the cartilage was transplanted into the in vitro cultures, it was found that the cartilage from nasal septum grew as nearly as it did in vivo.
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A human skeleton (endoskeleton) Osteology, derived from the Greek words osteon .(bone) and logos (knowledge), is the scientific study of bones, practised by osteologists. A subdiscipline of anatomy, anthropology, and paleontology, osteology is a detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, function, disease, pathology, the process of ossification (from cartilaginous molds), and the resistance and hardness of bones (biophysics). A person who examines bones and determines cause of death is a forensic anthropologist.
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Retrieved 2009-02-21 It does not show definite air-floats.Jones, W.E. 1964. The British Phycological Society. A key to the genera of the British Seaweeds. Reprinted from Field Studies Volume 1, (4) pp 1 - 32 All species’ sporophytes consist of a ramified holdfast, an unbranched cylindrical stipe, and a blade with a percurrent, cartilaginous midrib, Alaria is frequently found with lacerations running from the margin to the midrib caused by the ravages of the sea.
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Some groups within this superfamily possess a shell in the adult stage, some are without a shell in the adult stage, and others have developed a relatively tough gelatinous, cartilaginous internal structure, a sort of fake shell called the pseudoconch. The lateral and posterior foot lobes are joined as a ciliated proboscis that leads to the mouth, and the wings are united ventrally to form a single plate. A more general description is given under the entry sea butterfly.
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Extensive article on the role of menhaden in the ecosystem and possible results of overfishing. In addition to these bony fish, four types of cartilaginous fishes are also filter feeders. The whale shark sucks in a mouthful of water, closes its mouth and expels the water through its gills. During the slight delay between closing the mouth and opening the gill flaps, plankton is trapped against the dermal denticles which line its gill plates and pharynx.
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Species should not be grouped purely by morphologic or genetic similarity. Because a plesiomorphic character inherited from a common ancestor can appear anywhere in a phylogenetic tree, its presence does not reveal anything about the relationships within the tree.. Thus grouping species requires distinguishing ancestral from derived character states. An example to illustrate this is the breathing via gills in bony fish and cartilaginous fish. They share it because it was present in their common ancestor.
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A flying squirrel gliding Flying squirrels are not capable of flight like birds or bats; instead, they glide between trees. They are capable of obtaining lift within the course of these flights, with flights recorded to . The direction and speed of the animal in midair are varied by changing the positions of its limbs, largely controlled by small cartilaginous wrist bones. There is a cartilage projection from the wrist that squirrel holds upwards during a glide.
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Dwykaselachus (pronounced dwike-a-selak-us) is an extinct genus of symmoriid, a cartilaginous fish that lived in what is now South Africa during the Permian period around 280 million years ago. It was first discovered in the 1980s, in a nodule of sediments from the Karoo Supergroup. Dwykaselachus was named based on Dwyka Group, the group of sedimentary geological formation in the southeastern part of Africa. It represents the place where the type species Dwykaselachus oosthuizeni was found.
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Hagfish have no true fins and have six or eight barbels around the mouth and a single nostril. Instead of vertically articulating jaws like Gnathostomata (vertebrates with jaws), they have a pair of horizontally moving structures with tooth-like projections for pulling off food. The mouth of the hagfish has two pairs of horny, comb-shaped teeth on a cartilaginous plate that protracts and retracts. These teeth are used to grasp food and draw it toward the pharynx.Hyperotreti.
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Many fossils are known from the Nacimiento Formation, although bone is often altered into phosphatic concretions. Fossils belonging to a number of different organisms have been found here, including: plants (mostly dicotyledonous angiosperms),Anderson 1960 gastropods, freshwater bivalves,Hartman 1981 cartilaginous fish and bony fish, salamanders, turtles, champsosaurs, amphisbaenians, lizards, snakes, crocodilians,Sullivan and Lucas 1986 birds, and a variety of archaic mammals. Mammalian groups represented include multituberculates, didelphid marsupials, insectivorans, plesiadapiforms, carnivorans, taeniodonts, mesonychids, condylarths, and cimolestans.
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Cartilaginous fishes, such as this cloudy catshark, constitute a substantial portion of the blotchy swellshark's diet. Like other members of its genus, when threatened the blotchy swellshark is capable of rapidly inflating its stomach with water or air. This allows the shark to wedge itself inside a rocky crevice, becoming extremely difficult to remove. This species is an opportunistic, highly voracious predator; one recorded female long had 10 fish about long and 15 squid about long in her stomach.
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Frogspawn development. The larvae that emerge from the eggs, known as tadpoles (or occasionally polliwogs), typically have oval bodies and long, vertically flattened tails. As a general rule, free-living larvae are fully aquatic, but at least one species (Nannophrys ceylonensis) has semiterrestrial tadpoles which live among wet rocks. Tadpoles lack eyelids and have cartilaginous skeletons, lateral line systems, gills for respiration (external gills at first, internal gills later), and vertically flattened tails they use for swimming.
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The cartilaginous part of the Eustachian tube is about 24 mm in length and is formed of a triangular plate of elastic fibrocartilage, the apex of which is attached to the margin of the medial end of the bony part of the tube, while its base lies directly under the mucous membrane of the nasal part of the pharynx, where it forms an elevation, the torus tubarius or cushion, behind the pharyngeal opening of the auditory tube. The upper edge of the cartilage is curled upon itself, being bent laterally so as to present on transverse section the appearance of a hook; a groove or furrow is thus produced, which is open below and laterally, and this part of the canal is completed by fibrous membrane. The cartilage lies in a groove between the petrous part of the temporal bone and the great wing of the sphenoid; this groove ends opposite the middle of the medial pterygoid plate. The cartilaginous and bony portions of the tube are not in the same plane, the former inclining downward a little more than the latter.
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The stomach is reduced in size and surrounded by deposits of adipose tissue allowing for adequate energy to be stored. The skull is mostly cartilaginous and not well-ossified, unlike the adults of most larger ictalurids. The lateral line is fragmented and reaches to between the anterior to the posterior end of the adipose fin. This species also has a few paedomorphic traits (indicated by small size which ranges from 16-89mm, kidney morphology, and weak ossification of the skeleton).
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The Edestidae are a poorly known, extinct family of shark-like eugeneodontid holocephalid cartilaginous fish. Similar to the related family Helicoprionidae, members of this family possessed a unique "tooth-whorl" on the symphysis of the lower jaw and pectoral fins supported by long radials. In addition to having a tooth-whorl on the lower jaw, at least one species of the genus Edestus had a second tooth-whorl in the upper jaw. The palatoquadrate was either fused to the skull or reduced.
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Electroreception (or electroception) is the ability to detect electric fields. Several species of fish, sharks, and rays have the capacity to sense changes in electric fields in their immediate vicinity. For cartilaginous fish this occurs through a specialized organ called the Ampullae of Lorenzini. Some fish passively sense changing nearby electric fields; some generate their own weak electric fields, and sense the pattern of field potentials over their body surface; and some use these electric field generating and sensing capacities for social communication.
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Raja is a genus of skates in the family Rajidae containing 16 species. Formerly a wastebasket genus, many species historically placed here have been moved to other genera in the family, such as Amblyraja, Beringraja, Dipturus, Leucoraja and Rostroraja. Raja are flat-bodied, cartilaginous fish with a rhombic shapes due to their large pectoral fins extending from or nearly from the snouts to the bases of their tails. Their sharp snouts are produced by a cranial projection of rostral cartilage.
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Janusiscus schultzei was a gnathostome (jawed vertebrate) dating from the Early Devonian period in Siberia, approximately 415 million years ago. It may be a common ancestor of either Chondrichthyes (cartilaginous fish) or Osteichthyes (bony fish) or both. If it is an ancestor to both types of fish, then J. schultzei would also be a common ancestor to all living jawed vertebrates. The species name is in honor of Hans-Peter Schultze; the genus named after Janus, the Roman god of duality.
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The ulna is ossified from three centers: one each for the body, the wrist end, and the elbow end, near the top of the olecranon. Ossification begins near the middle of the body of the ulna, about the eighth week of fetal life, and soon extends through the greater part of the bone. At birth, the ends are cartilaginous. About the fourth year or so, a center appears in the middle of the head, and soon extends into the ulnar styloid process.
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One method of producing cartilage is to induce it from iPS cells. Alternatively, it is possible to convert fibroblasts directly into induced chondrogenic cells (iChon) without an intermediate iPS cell stage, by inserting three reprogramming factors (c-MYC, KLF4 and SOX9). Human iChon cells expressed marker genes for chondrocytes (type II collagen) but not fibroblasts. Implanted into defects created in the articular cartilage of rats, human iChon cells survived to form cartilaginous tissue for at least four weeks, with no tumors.
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It is encompassed inside a bony or cartilaginous capsule which opens into the base of the nasal cavity. Animals that exhibit flehmen have a papilla located behind the incisors and ducts which connect the oral cavity to the VNO, with horses being an exception. Horses exhibit flehmen but do not have an incisive duct communication between the nasal and oral cavity because they do not breathe through their mouths; instead, the VNOs connect to the nasal passages by the nasopalatine duct.
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Balbacua has numerous variations when it comes to the spices and secondary ingredients used. A common aspect of the dish, however, is the use of collagen-rich parts of beef, including oxtail, skin, knuckles, and other cartilaginous beef cuts in addition to regular beef cuts. These are cooked for around four to six hours until the meat is falling off the bones and is very tender. The collagen from the skin and cartilage thickens the soup into a gelatinous consistency.
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The skeleton is cartilaginous. The notochord is gradually replaced by a vertebral column during development, except in Holocephali, where the notochord stays intact. In some deepwater sharks, the column is reduced.Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date As they do not have bone marrow, red blood cells are produced in the spleen and the epigonal organ (special tissue around the gonads, which is also thought to play a role in the immune system).
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Nautiluses are the only extant cephalopods with a true external shell. However, all molluscan shells are formed from the ectoderm (outer layer of the embryo); in cuttlefish (Sepia spp.), for example, an invagination of the ectoderm forms during the embryonic period, resulting in a shell (cuttlebone) that is internal in the adult. The same is true of the chitinous gladius of squid and octopuses. Cirrate octopods have arch-shaped cartilaginous fin supports, which are sometimes referred to as a "shell vestige" or "gladius".
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The holotype (and only known specimen) of S. caillieti is an immature female collected on September 23, 1995 by Leonard Compagno and Peter Last. It was originally identified tentatively as a Taiwan angelshark (S. formosa), before being described as a new species by Jonathan Walsh, David Ebert, and Leonard Compagno in a 2011 issue of the scientific journal Zootaxa. It was named in honor of ichthyologist Gregor Cailliet, particularly known for his studies of growth and aging in cartilaginous fishes.
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During the early Paleozoic, southern and western New Mexico were submerged by a warm shallow sea that would come to be home to creatures including brachiopods, bryozoans, cartilaginous fishes, corals, graptolites, nautiloids, placoderms, and trilobites. During the Ordovician the state was home to algal reefs up to 300 feet high. During the Carboniferous, a richly vegetated island chain emerged from the local sea. Coral reefs formed in the state's seas while terrestrial regions of the state dried and were home to sand dunes.
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Janassa is an extinct genus of petalodont cartilaginous fish that lived in marine environments in what is now central United States of America and Europe during the Carboniferous and upper Permian. It is known from teeth and a few poorly preserved body fossils from Germany (Kupferschiefer, Upper Permian) and England (Marl Slate, Upper Permian). According to the fossils, Janassa had a body plan very similar to that of the modern skate. Its teeth suggest it crushed and ate shellfish, such as brachiopods.
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Elasmobranchii is one of the two subclasses of cartilaginous fish in the class Chondrichthyes, the other being Holocephali (chimaeras). Members of the elasmobranchii subclass have no swim bladders, five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins, and small placoid scales. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper. Extant elasmobranchs exhibit several archetypal jaw suspensions: amphistyly, orbitostyly, hyostyly, and euhyostyly.
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Both the holotype and AMNH 7002 “Eumatthevia” have been studied and restudied, with additions and modifications to the cranial description. The nares and orbit of Mycterosaurus are unusually large, with the orbit directed outwardly and circular in manner. The extremely large size of the orbit has been associated with the relatively small size of the animal. Additionally, the surface of the supraoccipital that articulates with the parietals dorsally above are cartilaginous, a condition found in that of crocodiles, lizards, and dinosaurs.
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Batoids are a superorder of cartilaginous fish consisting of skates, rays and other fish all characterized by dorsoventrally flattened bodies and large pectoral fins fused to the head. This distinctive morphology has resulted in several unique forms of locomotion. Most Batoids exhibit median paired fin swimming, utilizing their enlarged pectoral fins. Batoids that exhibit median paired fin swimming fall somewhere along a spectrum of swimming modes from mobuliform to rajiform based on the number of waves present on their fin at once.
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The Mexican stoneroller has a very stout body with a very large head and snout. The mouth is unique in that its teeth have cartilaginous sheaths, while the size of its mouth is usually very small. The fish's mature length can range anywhere from 3 to nearly 6 inches, however 6 inches is rare, and the average is about 3.5 inches. They have small scales that run along the lateral line, much like the Gila longfin dace and the Yaqui longfin dace.
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Suckers use their cartilaginous jaws to scrape the algae and detritus off the stones at the bottom, and despite any shortages of these foods, suckers show little seasonal movement. Diatoms, detritus, algae, and other organic debris have been found in the gut. They are unique in that they are the only members of the genus to hybridize with other members of the same genus, increasing gene flow among species. They can also live to be more than 20 years old.
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Deltoptychius is an extinct species of cartilaginous fish related to the modern chimaeras. It lived in the Carboniferous period of present-day United Kingdom. Fossils of the genus have been found in the Glencartholm Volcanic Beds Formation of the Upper Border Group in Scotland. Although it emerged over 300 million years ago, Deltoptychius was similar in appearance to modern-day chimaeras, possessing a long, whip-like tail and large, wing-like pectoral fins that it probably used to glide through the water.
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Pescetarianism (provided the fish is ruled kosher) conforms to Jewish dietary laws, as kosher fish is "pareve"—neither "milk" nor "meat". In essence, aquatic animals such as mammals like dolphins and whales are not kosher, nor are cartilaginous fish such as sharks and rays, since they all have dermal denticles and not bony- fish scales. In 2015, members of the Liberal Judaism synagogue in Manchester founded The Pescetarian Society, citing pescetarianism as originally a Jewish diet, and pescetarianism as a form of vegetarianism.
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Despite its relatively small size, the sharpnose sevengill shark is considered a top predator in the ecosystem it inhabits. At the Great Meteor Seamount in the eastern Atlantic, this species feeds primarily on teleosts and cephalopods, and to a lesser extent on small cartilaginous fishes. Off Tunisia, crustaceans are the second-most common prey taken after teleosts. Off Australia, this species consumes mostly teleosts, with smaller individuals taking mainly Lepidorhynchus denticulatus and larger individuals taking increasing numbers of snake mackerels and cutlassfishes.
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Agar is a gelatinous substance that is commercially used as an incubation matrix for microbes and other products that require an ecologically friendly gelatinous matrix. G. amansii can be purple, red, to yellowish-red because it contains the class of pigments known as phycobiliprotein. Its branching body is cartilaginous and can grow up to a height of 8 to 30 cm or 3 to 12 in. G. amansii may have four or five opposite, compound-lobed, pinnate leaves on each branch.
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Most vertebrates have some form of duct to transfer the sperm from the testes to the urethra. In cartilaginous fish and amphibians, sperm is carried through the archinephric duct, which also partially helps to transport urine from the kidneys. In teleosts, there is a distinct sperm duct, separate from the ureters, and often called the vas deferens, although probably not truly homologous with that in humans. The vas deferens loops over the ureter in placental mammals, but not in marsupial mammals.
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In mammals, the neocerebellum is the major part of the cerebellum by mass, but, in other vertebrates, it is typically the spinocerebellum. The cerebellum of cartilaginous and bony fishes is extraordinarily large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei. Instead, the primary targets of Purkinje cells are a distinct type of cell distributed across the cerebellar cortex, a type not seen in mammals.
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Juvenile Izak catsharks are boldly patterned with many irregularly shaped dark brown spots on a light yellow to yellowish brown background. The spots enlarge and fuse with age to form an intricate pattern of reticulations and U-shaped markings in adults. The underside is plain white, with obvious black sensory pores beneath the head, body, and paired fins. Like other Holohalaelurus species, but contrary to the pattern in most cartilaginous fishes, males attain a much greater maximum length than females: versus .
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The swim bladder in these fish is reduced, and the skull is mostly cartilaginous and not well-ossified, unlike the adults of most larger ictalurids. The lateral line is fragmentary and never reaches past the anterior part of the anal fin. This species also has a few paedomorphic traits (indicated by small size, kidney morphology, and weak ossification of the skeleton). This species grows to about TL. The widemouth blindcat is a vulnerable species, and is threatened by groundwater pollution.
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Cladodus is an extinct genus of cartilaginous fishes in the family Cladoselachidae. As the name implies, they are a type of cladodont, primitive sharks with teeth designed to snag fish and swallow them whole, instead of sawing off chunks to swallow. Fossils of Cladodus have been found in Barkip, Scotland and in the Pitkin Formation (Carboniferous period) in Arkansas, United States. In addition, fossils attributable to Cladodus are known from the Manning Canyon Shale of Carboniferous age in the state of Utah.
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Frog larvae are known as tadpoles and typically have oval bodies and long, vertically flattened tails with fins. The free-living larvae are normally fully aquatic, but the tadpoles of some species (such as Nannophrys ceylonensis) are semi-terrestrial and live among wet rocks. Tadpoles have cartilaginous skeletons, gills for respiration (external gills at first, internal gills later), lateral line systems and large tails that they use for swimming. Newly hatched tadpoles soon develop gill pouches that cover the gills.
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The fruit is composed of the receptacle or upper end of the flower-stalk (the so- called calyx tube) greatly dilated. Enclosed within its cellular flesh is the true fruit: five 'cartilaginous' carpels, known colloquially as the "core". From the upper rim of the receptacle are given off the five sepals, the five petals, and the very numerous stamens. Pears and apples cannot always be distinguished by the form of the fruit; some pears look very much like some apples, e.g.
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When detecting seismic signals, the animals lean forward and put more weight on their larger front feet; this is known as the "freezing behaviour". Elephants possess several adaptations suited for seismic communication. The cushion pads of the feet contain cartilaginous nodes and have similarities to the acoustic fat found in marine mammals like toothed whales and sirenians. A unique sphincter-like muscle around the ear canal constricts the passageway, thereby dampening acoustic signals and allowing the animal to hear more seismic signals.
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In amphibians, the telencephalon distinctly shows medial, dorsal, lateral and ventral parts of the pallium, plus striatal, pallidal, diagonal and preoptic parts of the basal nuclei. However, the pallial portions do not show a visible lamination. They already have a mixture of glutamatergic (excitatory) and GABAergic (inhibitory) neurons, whereas the subpallium is largely populated by inhibitory neurons. This structure is very similar to that found generally in anamniotes, though cartilaginous fishes do show a layered arrangement of their pallial neurons.
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The inner ear of Seymouria baylorensis retains a cochlear recess located behind (rather than below) the vestibule, and its anterior semicircular canal was likely encompassed by a cartilaginous (rather than bony) supraoccipital. These features are more primitive than those of true reptiles and synapsids. The palate (roof of the mouth) had some similarities with both amniote and non-amniote tetrapods. On the one hand, it retained a few isolated fangs with maze-like internal enamel folding, as is characteristic for "labyrinthodont" amphibians.
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Such a skeleton is present in echinoderms and chordates. The poriferan 'skeleton' consists of microscopic calcareous or siliceous spicules or a spongin network. The Coleoidae do not have a true endoskeleton in the evolutionary sense; there, a mollusk exoskeleton evolved into several sorts of internal structure, the "cuttlebone" of cuttlefish being the best-known version. Yet they do have cartilaginous tissue in their body, even if it is not mineralized, especially in the head, where it forms a primitive cranium.
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Water is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs more light than air does. The body of a fish is divided into a head, trunk and tail, although the divisions between the three are not always externally visible. The skeleton, which forms the support structure inside the fish, is either made of cartilage (cartilaginous fish) or bone (bony fish). The main skeletal element is the vertebral column, composed of articulating vertebrae which are lightweight yet strong.
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Fish have the simplest circulatory system, consisting of only one circuit, with the blood being pumped through the capillaries of the gills and on to the capillaries of the body tissues. This is known as single cycle circulation. In the adult fish, the four compartments are not arranged in a straight row, instead forming an S-shape with the latter two compartments lying above the former two. This relatively simpler pattern is found in cartilaginous fish and in the ray-finned fish.
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Tracheal collapse Tracheal stent in a dog Tracheal collapse in dogs is a condition characterized by incomplete formation or weakening of the cartilaginous rings of the trachea resulting in flattening of the trachea. It can be congenital or acquired, and extrathoracic or intrathoracic (inside or outside the thoracic cavity). Tracheal collapse is a dynamic condition. Collapse of the cervical trachea or extrathoracic (in the neck) occurs during inspiration; collapse of the thoracic trachea or intrathoracic (in the chest) occurs during expiration.
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See MMA external link for an example of Wenzel's work Silversmiths made covered cups and richly wrought ewers and platters, strictly for display, perhaps incorporating the large sea-shells now being brought back from the tropics, which were "cherished as Art produced by Nature".Fuchs, 34 In the Netherlands a uniquely anamorphic "auricular style", employing writhing and anti-architectural cartilaginous motifs was developed by the van Vianen family of silversmiths.Rijksmuseum , "Paulus van Vianen", Van Vianem cup. Waddesdon Manor enamel and jewels.
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Restoration Stenonychosaurus had one of the largest known brains of any dinosaur, relative to its body mass (comparable to modern birds). This has been calculated as a cerebrum-to-brain- volume ratio 31.5% to 63% of the way from a non-avian reptile proportion to a truly avian one. Additionally, it had bony cristae supporting their tympanic membranes that were ossified at least in their top and bottom regions. The rest of the cristae were either cartilaginous or too delicate to be preserved.
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Skates are cartilaginous fishes like other Chondrichthyes, however, skates, like rays and other Rajiformes, have a flat body shape with flat pectoral fins that extend the length of their body. A large portion of the skate's dorsal body is covered by rough skin made of placoid scales. Placoid scales have a pointed tip that is oriented caudally and are homologous to teeth. Their mouths are located on the underside of the body, with a jaw suspension common to Batoids known as euhyostyly.
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Earwax Dry-type earwax World map of the distribution of the A allele of the single nucleotide polymorphism rs17822931 in the ABCC11 gene assorted with dry-type earwax. The proportion of A alleles (dry-type earwax) in each population is represented by the white area in each circle. Cerumen is produced in the outer third of the cartilaginous portion of the ear canal. It is a mixture of viscous secretions from sebaceous glands and less- viscous ones from modified apocrine sweat glands.
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Their elasticity allows rib cage movement for respiratory activity. The phrase floating rib or vertebral rib () refers to the two lowermost, the eleventh and twelfth rib pairs; so-called because they are attached only to the vertebrae–and not to the sternum or cartilage of the sternum. These ribs are relatively small and delicate, and include a cartilaginous tip. The spaces between the ribs are known as intercostal spaces; they contain the intercostal muscles, and neurovascular bundles containing nerves, arteries, and veins.
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In amphibians and lungfishes, the oviduct is a simple ciliated tube, lined with mucus-secreting glands that produce the jelly that surrounds the ovum. In all other vertebrates, there is normally some degree of specialisation of the tube, depending on the type of eggs produced. In cartilaginous fishes, the middle portion of the tube develops as a shell gland. The first portion of this gland secretes the egg white, while the lower portion secretes a hard, horny, capsule to protect the developing egg.
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Rajiformes is one of the four orders in the superorder Batoidea, flattened cartilaginous fishes related to sharks. Rajiforms are distinguished by the presence of greatly enlarged pectoral fins, which reach as far forward as the sides of the head, with a generally flattened body. The undulatory pectoral fin motion diagnostic to this taxon is known as rajiform locomotion. The eyes and spiracles are located on the upper surface of the head and the gill slits are on the underside of the body.
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Demand for their gill rakers, the cartilaginous structures protecting the gills, has recently entered Chinese medicine. To fill the growing demand in Asia for gill rakers, targeted fisheries have developed in the Philippines, Indonesia, Mozambique, Madagascar, India, Pakistan, Sri Lanka, Brazil, and Tanzania. Each year, thousands of manta rays, primarily M. birostris, are caught and killed purely for their gill rakers. A fisheries study in Sri Lanka and India estimated that over 1000 were being sold in the country's fish markets each year.
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Like most prehistoric cartilaginous fishes, E. kawai is known from a few fragmentary remains, including teeth and a beak. E. kawai provided many new points of knowledge for scientists when it was formally described in 2006. Firstly, the range of the prehistoric Edaphodon species, and indeed all prehistoric rabbitfish, was thought to be restricted to the Northern Hemisphere. However, when the fragmental remains of E. kawai were discovered in the Chatham Islands not far from New Zealand, the rabbitfish range was extended.
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Tracheas are an important area of the respiratory tract; aside from directing air in and out of the lungs, it has the largest volume of dead space in the tract. Dead space in avians is around 4.5 times higher in mammals of roughly the same size. In particular, flamingos have a trachea that is longer than its body length with 330 cartilaginous rings. As a result, they have a calculated dead space twice as high as another bird of the same size.
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Electroreceptors (ampullae of Lorenzini) and lateral line canals in the head of a shark Inner view of Ampullae of Lorenzini The ampullae of Lorenzini are special sensing organs called electroreceptors, forming a network of jelly- filled pores. They are mostly discussed as being found in cartilaginous fish (sharks, rays, and chimaeras); however, they are also reported to be found in Chondrostei such as reedfish and sturgeon. Lungfish have also been reported to have them. Teleosts have re-evolved a different type of electroreceptors.
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In life, J. kerwoodi resembled a lamprey with a very small mouth. Because the fossil had no teeth, teeth-like structures, nor suggestions of either in its mouth, it was not carnivorous like many modern lampreys. It was more likely to have been a filter-feeder or a detritus-feeder, possibly in the manner of larval lampreys. The fish had a cartilaginous skeleton, and a branchial basket resembling the cyclostomes - features that suggest that it was a basal member of that clade.
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In the simplest sense, craniates are chordates with well-defined heads, thus excluding members of the chordate subphyla Tunicata (tunicates) and Cephalochordata (lancelets), but including Myxini, which have cartilaginous skulls and tooth-like structures composed of keratin. Craniata also includes all lampreys and armoured jawless fishes, armoured fish, sharks, skates, and rays, and teleostomians: spiny sharks, bony fish, lissamphibians, temnospondyls and protoreptiles, sauropsids and mammals. The craniate head consists of a brain, sense organs, including eyes, and a skull.Campbell & Reece 2005 pp.
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The most common dinosaur in the paleoenvironment preserved in the Antlers Formation is the ornithopod Tenontosaurus. Other vertebrates present at the time of Astrodon included the amphibian Albanerpeton arthridion, the reptiles Atokasaurus metarsiodon and Ptilotodon wilsoni, the crurotarsan reptile Bernissartia, the cartilaginous fish Hybodus buderi and Lissodus anitae, the ray-finned fish Gyronchus dumblei, the crocodilian Goniopholis, and the turtles Glyptops and Naomichelys.Nydam, R. L. and R. L. Cifelli. 2002a. Lizards from the Lower Cretaceous (Aptian–Albian) Antlers and Cloverly formations.
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Schizorhiza is a fossil genus of cartilaginous fish, containing a single accepted species Schizorhiza stromeri. Its fossils are found in rocks dating from the Campanian and Maastrichtian stages; it thus lived between about and million years ago. Like other sawfish-like rays from the Mesozoic, it probably did not survive the Cretaceous–Paleogene extinction event; there are a few remains from the Paleogene but these seem to have been reworked from Late Cretaceous deposits. (2002): Schizorhiza: a unique sawfish paradigm from the Difunta Group, Coahuila, Mexico.
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FMNH PR 2379 is essentially complete, including some cartilaginous elements, but is somewhat weathered. The skeleton is articulated and is preserved on a limestone slab, on which it is exposed in ventral view. It can be distinguished from other iguanians by details of the skull and lower jaw, the form of the ribs, and the location of the autotomy planes in the tail vertebrae (the features that allow tail separation). It was a small animal, with the thigh bones being shorter than in length.
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They are nearly equal in width throughout or slightly ventricose in age, with a spacing that is close to subdistant. About 18–24 gills reach the stem, with two tiers of lamellulae (short gills that do not extend fully from the cap margin to the stem) that may develop veins running between them. The gills are white to creamy-white with edges that are even and whitish, and waxy in appearance and consistency. The stem is long, thick, equal, tubular, somewhat elastic, cartilaginous, and not particularly fragile.
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Dogfishes (pictured: Squalus mitsukurii) are included in the diet of the bignose shark. The bignose shark feeds mainly on bottom-dwelling bony fishes (including lizardfishes, croakers, flatfishes, and batfishes), cartilaginous fishes (including Squalus dogfishes, Holohalaelurus catsharks, Dasyatis stingrays, and chimaeras), and cephalopods. In turn, juveniles may potentially fall prey to larger sharks. Like other requiem sharks, this species is viviparous: when the developing embryos exhaust their supply of yolk, the depleted yolk sac is converted into a placental connection through which the mother delivers nourishment.
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According to De Silva, there are 60 sharks species and 30 rays and skates found around the coast of Sri Lanka. Sharks are a group of fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. The following list of shark species recorded from the territorial waters of Sri Lanka.
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Acanthodians are often referred to as "spiny sharks"; though they are not part of Chondrichthyes proper, they are a paraphyletic assemblage leading to cartilaginous fish as a whole. Since then, sharks have diversified into over 500 species. They range in size from the small dwarf lanternshark (Etmopterus perryi), a deep sea species of only in length, to the whale shark (Rhincodon typus), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths of .
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This allows more efficient locomotion among these negatively buoyant cartilaginous fish. By contrast, most bony fish possess a homocercal caudal fin. Tiger sharks have a large upper lobe, which allows for slow cruising and sudden bursts of speed. The tiger shark must be able to twist and turn in the water easily when hunting to support its varied diet, whereas the porbeagle shark, which hunts schooling fish such as mackerel and herring, has a large lower lobe to help it keep pace with its fast-swimming prey.
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The koala has a cartilaginous pad at the end of the spine that may make it more comfortable when it perches in the fork of a tree. Mounted skeleton The koala has one of the smallest brains in proportion to body weight of any mammal, being 60% smaller than that of a typical diprotodont, weighing only on average. The brain's surface is fairly smooth, typical for a "primitive" animal. It occupies only 61% of the cranial cavity and is pressed against the inside surface by cerebrospinal fluid.
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These consist of a series of bony or cartilaginous cylindrical vertebrae, generally with neural arches that protect the spinal cord, and with projections that link the vertebrae. However hagfish have incomplete braincases and no vertebrae, and are therefore not regarded as vertebrates, but as members of the craniates, the group from which vertebrates are thought to have evolved. However the cladistic exclusion of hagfish from the vertebrates is controversial, as they may be degenerate vertebrates who have lost their vertebral columns. The position of lampreys is ambiguous.
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Ramariopsis was originally defined as a subgenus of Clavaria by Dutch mycologist Marinus Anton Donk in 1933. Several European species similar to the type, Clavaria kunzei, were included: Clavaria subtilis, Clavaria pyxidata, Clavaria angulispora, and Clavaria pulchella. In Donk's concept, defining characteristics of the group included small, branching, fruitbodies with a stipe, and an almost cartilaginous consistency to the flesh. Spores are small and hyaline (translucent), spherical to ellipsoid, and have a surface ornamentation ranging from echinulate (spiny) to verruculose (covered with small warts).
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Corticium candelabrum is sometimes thinly encrusting, or may form small solid cushions some across and high which are connected to the substrate by a narrow solid stalk. The surface is sometimes irregularly lobed and is smooth and shiny, and covered by a translucent envelope. The oscula (exhalant openings) are slightly raised and the pores (inhalant openings) are few in number but quite noticeable. The colour is some shade of pale to mid- brown, sometimes tinged with red, and its consistency varies from firm to cartilaginous.
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Most rhinesuchids are only known from skull material, although a few members of the group (Uranocentrodon, Broomistega, and Australerpeton, for example) include specimens preserving a significant portion of the rest of the skeleton. A juvenile specimen of Broomistega had ankles and vertebrae which were poorly ossified, indicating that its joints had a large amount of cartilaginous material to supplement the low amount of bone. This trait is often correlated with an aquatic lifestyle. Features of the skull, such as upwards-pointing eyes, also support this hypothesis.
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Ischyodus is an extinct genus of cartilaginous fish belonging to the subclass Holocephali, which includes the modern-day chimaeras. Fossils are known from Europe (including Russia), North America, and New Zealand. Ischyodus was rather similar to the present-day chimaera Chimaera monstrosa, which is found in the Atlantic Ocean and Mediterranean Sea. Just like C. monstrosa, Ischyodus had large eyes, a long whip-like tail, small lips, large pectoral fins and dorsal fin, and a dorsal spike attached to the front of the dorsal fin.
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Rather slow-swimming, the pyjama shark spends most of the day resting in caves or crevices or amongst kelp, emerging at night to actively forage for food. Many individuals may congregate at a single spot, particularly in summer. This species falls prey to larger sharks, and is one of the cartilaginous fish most frequently consumed by the broadnose sevengill shark (Notorynchus cepedianus). When threatened, it often curls into a circle with its tail covering its head, in a similar fashion to the shysharks (Haploblepharus).
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Limb formation begins in the morphogenetic limb field. Limb formation results from a series of reciprocal tissue interactions between the mesenchyme of the lateral plate mesoderm and the overlying ectodermally derived epithelial cells. Cells from the lateral plate mesoderm and the myotome migrate to the limb field and proliferate to the point that they cause the ectoderm above to bulge out, forming the limb bud. The lateral plate cells produce the cartilaginous and skeletal portions of the limb while the myotome cells produce the muscle components.
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The deep petrosal nerve is a branch of the internal carotid plexus which runs through the carotid canal lateral to the internal carotid artery. It enters the cartilaginous substance which fills the foramen lacerum, and joins with the greater petrosal nerve to form the nerve of the pterygoid canal, also known as the Vidian nerve. The deep petrosal nerve carries postganglionic sympathetic axons to the pterygopalatine ganglion, which pass through without synapsing. These axons innervate blood vessels and mucous glands of the head and neck.
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The maxilloturbinates may not have been preserved because they were either very thin or cartilaginous. The possibility has also been raised that these ridges are associated with an olfactory epithelium rather than turbinates. Nonetheless, the possible presence of maxilloturbinates suggests that Glanosuchus may have been able to rapidly breathe without drying out the nasal passage, and therefore could have been an endotherm. Glanosuchus is the earliest known therapsid to possess maxilloturbinates, but it shares features with reptiles that suggest it was not fully endothermic.
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A fuzzy velvet antler during summer growth Velvet antler is the whole cartilaginous antler in a precalcified growth stage of the Cervidae family including the species of deer such as elk, moose, and caribou. Velvet antler is covered in a hairy, velvet-like "skin" known as velvet and its tines are rounded, because the antler has not calcified or finished developing. Velvet antler preparations are sold in China as part of traditional Chinese medicine, and in the United States and some other countries as a dietary supplement.
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Cutaway diagram showing various organs of a fish The body of a fish is divided into a head, trunk and tail, although the divisions between the three are not always externally visible. The skeleton, which forms the support structure inside the fish, is either made of cartilage, in cartilaginous fish, or bone in bony fish. The main skeletal element is the vertebral column, composed of articulating vertebrae which are lightweight yet strong. The ribs attach to the spine and there are no limbs or limb girdles.
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The sparsely-spotted stingaree is common in areas covered by sand or seagrass. One of the most abundant cartilaginous fishes off southern Australia, the sparsely-spotted stingaree has a relatively wide distribution extending from Crowdy Head in New South Wales to Lancelin in Western Australia, including the entirety of Tasmania. Its range has expanded southward in the past few decades, apparently due to climate change. In Port Phillip, its numbers increased from 1970 to 1991, likely as a result of fisheries depleting its ecological competitors.
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This species shares the southern extent of its range with the banded stingaree (U. cruciatus). The two species apparently hybridize, highly unusual for cartilaginous fish, and produce offspring that are intermediate in color pattern. In a 2007 study of 388 fishes, these two species were the only two that could not be distinguished on the basis of their cytochrome c gene sequences, attesting to a close evolutionary relationship. Almost the entire range of the yellowback stingaree is under pressure from Australian Commonwealth and State-managed commercial fisheries.
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The barndoor skate (Dipturus laevis) is a species of marine cartilaginous fish in the skate family Rajidae of the order Rajiformes. It is native to the northwestern Atlantic Ocean, and is found from the Grand Banks of Newfoundland and the southern side of the Gulf of St. Lawrence south to North Carolina. The fish is one of the largest skates found in the North Atlantic Ocean, reaching lengths up to . It is carnivorous, feeding on invertebrates and other fish found near the sea floor.
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In life, the knobs would have been covered by tough cartilaginous or keratinous integument, which would have made them appear even larger. Carpal spurs and knobs are also known from other extant as well as extinct birds. Within Columbidae, the crowned pigeons and the Viti Levu giant pigeon have outgrowths on the carpometacarpus which are similar to those of the female Rodrigues solitaire. Other well known examples are the steamer ducks, the torrent duck, sheathbills, screamers, the spur-winged goose, and the extinct Jamaican ibis, Xenicibis xympithecus.
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In the cartilaginous fishes (class Chondrichthyes), sharks of the families Lamnidae (porbeagle, mackerel, salmon, and great white sharks) and Alopiidae (thresher sharks) exhibit endothermy. The degree of endothermy varies from the billfishes, which warm only their eyes and brain, to the bluefin tuna and the porbeagle shark, which maintain body temperatures in excess of above ambient water temperatures. Endothermy, though metabolically costly, is thought to provide advantages such as increased muscle strength, higher rates of central nervous system processing, and higher rates of digestion.
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The claspers of a spotted wobbegong shark (Orectolobus maculatus) The claspers of a young spinner shark (Carcharhinus brevipinna) In biology, a clasper is a male anatomical structure found in some groups of animals, used in mating. A close up view of a chimaera clasper (Hydrolagus collie). Note the many small tooth-like projections covering the exterior surface. Male cartilaginous fish have claspers formed from the posterior portion of their pelvic fin which serve as is used to channel semen into the female's cloaca during mating.
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Aetobatus narutobiei, the Naru eagle ray, is a species of cartilaginous fish of the eagle ray family, Myliobatidae. It is found in the northwest Pacific off south Japan, South Korea, China, Hong Kong and Vietnam. It occurs from shallow, coastal flats to a depth of , but always in water warmer than . Until 2013, this species was included in the longheaded eagle ray (Aetobatus flagellum), but the two differ in genetics, morphology, size and range (the smaller longhead eagle ray is from the Indian Ocean).
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Chimeras (Holocephali) have pavement teeth that are flat, hexagonal in shape and interconnect to form an even dental plate. There is the presence of calcified strengthened cartilaginous jaws, calcified struts within the jaws and a lever ‘nutcracker’ system that amplifies the force of the jaw adductor muscles. The fusion of the palatoquadrate and mandibular symphysis, a restricted gape and asynchronous activation of the jaw adductors are key elements in the ‘nutcracker’ model of jaw-crushing ability. Chimeras use their pavement teeth for grinding molluscs, gastropods and crabs.
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Although the sunfish descended from bony ancestors, its skeleton contains largely cartilaginous tissues, which are lighter than bone, allowing it to grow to sizes impractical for other bony fishes. Its teeth are fused into a beak-like structure, which prevents them from being able to fully close their mouths, while also having pharyngeal teeth located in the throat. The sunfish lacks a swim bladder. Some sources indicate the internal organs contain a concentrated neurotoxin, tetrodotoxin, like the organs of other poisonous tetraodontiformes, while others dispute this claim.
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The gill opening was closed off from below, the remaining opening was small and hole-like, and is termed a spiracle. The spiracle is still found in all cartilaginous fish except requiem sharks, hammerhead sharks, and chimaeras, and is found in some primitive bony fishes (coelacanth, sturgeon, paddlefish and bichirs). It is also seen as an otic notch in the skull of the extinct labyrinthodonts, and is thought to be associated with the ear opening in amniotes and frogs.Romer, A.S. (1949): The Vertebrate Body.
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Because of this, it has been proposed to be used for entire genome sequencing to represent the cartilaginous fish class. They are considered to resemble a cross between a shark and a ray or skate, but can be distinguished from sharks because they possess an operculum over their gill slits. Additionally, their skin is smooth, not covered in tough scales, characteristic of the shark. While the shark's jaw is loosely attached to the skull, the family Callorhinchidae differ in that their jaws are fused to their skulls.
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Lateral view of the face with a saddle nose deformity far up on the bridge due to granulomatosis with polyangiitis using a nasal prosthesis It can usually be corrected with augmentation rhinoplasty by filling the dorsum of nose with cartilage, bone or synthetic implant. If the depression is only cartilaginous, cartilage is taken from the nasal septum or auricle and laid in single or multiple layers. If deformity involves both cartilage and bone, cancellous bone from iliac crest is the best replacement. Autografts are preferred over allografts.
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The posterior edge of the scapula is robust and the acromion is lightly built, likely fused into a cartilaginous system with its periphery in life. The coracoid measures in length, it has a broad and convex lateral surface that forms a slightly inclined concavity near of the scapulocoracoid suture. This concavity bends down towards the scapular widening. Near the scapulocoracoid suture, this edge turns very thin and possibly into cartilage along with the periphery of the coracoid in life, as the case of the scapular edge.
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Normally, these are paired structures, but in birds and some cartilaginous fishes, one or the other side fails to develop (together with the corresponding ovary), and only one functional oviduct is found. Except in teleosts, the oviduct is not directly in contact with the ovary. Instead, the most anterior portion ends in a funnel-shaped structure called the infundibulum, which collects eggs as they are released by the ovary into the body cavity. The only female vertebrates to lack oviducts are the jawless fishes.
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Skull of Tiktaalik, an extinct genus transitional between lobe-finned fish and early tetrapods The skulls of the earliest tetrapods closely resembled those of their ancestors amongst the lobe-finned fishes. The skull roof is formed of a series of plate-like bones, including the maxilla, frontals, parietals, and lacrimals, among others. It is overlaying the endocranium, corresponding to the cartilaginous skull in sharks and rays. The various separate bones that compose the temporal bone of humans are also part of the skull roof series.
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Aspirin has been shown to have at least three additional modes of action. It uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria, by diffusing from the inner membrane space as a proton carrier back into the mitochondrial matrix, where it ionizes once again to release protons. Aspirin buffers and transports the protons. When high doses are given, it may actually cause fever, owing to the heat released from the electron transport chain, as opposed to the antipyretic action of aspirin seen with lower doses.
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Helicoprion is a genus of extinct, shark-like eugeneodontid holocephalid fish. Almost all fossil specimens are of spirally arranged clusters of the individuals' teeth, called "tooth whorls"— the cartilaginous skull, spine, and other structural elements have not been preserved in the fossil record, leaving scientists to make educated guesses as to its anatomy and behavior. Helicoprion lived in the oceans of the early Permian , with species known from North America, Eastern Europe, Asia, and Australia. The closest living relatives of Helicoprion (and other eugeneodontids) are the chimaeras.
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Sparassis crispa can be very tasty, but should be thoroughly cleaned before use, as the folds can contain dirt and other material, as it grows and envelops objects around it such as pine needles. Antonio Carluccio reports that European Sparassis crispa should be picked when creamy white, and once yellow are too indigestible to eat. It is good for drying and reconstituting, as it retains its cartilaginous texture and hence is good for soups. S. spathulata, a cauliflower mushroom which looks similar to Grifola frondosa, is edible.
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It blooms from May to November producing yellow flowers. The simple inflorescences occur singly in the axils and have obloid to shortly cylindrical flower-heads that are in length and wide and densely packed with golden flowers. Following flowering cartilaginous to subwoody seed pods form that have a linear shape with straight sides with a length of up to and wide and have finely longitudinal ridging. The glossy dark brown seeds inside are longitudinally arranged and have an elliptic-oblong shape with a length of .
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They are housed in cartilaginous capsules on either side of the cranium. They provide the squid with information on its body position in relation to gravity, its orientation, acceleration and rotation, and are able to perceive incoming vibrations. Without the statocysts, the squid cannot maintain equilibrium. Squid appear to have limited hearing, but the head and arms bear lines of hair-cells that are weakly sensitive to water movements and changes in pressure, and are analogous in function to the lateral line system of fish.
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Genetically modified fish (GM fish) are organisms from the taxonomic clade which includes the classes Agnatha (jawless fish), Chondrichthyes (cartilaginous fish) and Osteichthyes (bony fish) whose genetic material (DNA) has been altered using genetic engineering techniques. In most cases, the aim is to introduce a new trait to the fish which does not occur naturally in the species, i.e. transgenesis. GM fish are used in scientific research and kept as pets. They are being developed as environmental pollutant sentinels and for use in aquaculture food production.
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The prognosis is good for stable lesions (stage I and II) in juveniles with open growth plates; treated conservatively—typically without surgery—50% of cases will heal. Recovery in juveniles can be attributed to the bone's ability to repair damaged or dead bone tissue and cartilage in a process called bone remodeling. Open growth plates are characterized by increased numbers of undifferentiated chondrocytes (stem cells) which are precursors to both bone and cartilaginous tissue. As a result, open growth plates allow for more of the stem cells necessary for repair in the affected joint.
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Research has yet to define a correlation between these ridges and the evidence of turbinates, mostly based on the assumption that they were probably cartilaginous and difficult to preserve. The lack of intact skulls in these early mammals also serves as an impediment to study. The skull of Brasilitherium held more promising results, as it contained a secondary palate separating the nose from the mouth, thereby enhancing skeletal durability and preservation of the turbinate structure. Researchers identified small shards of bone inside the skull’s nasal cavity that were assumed to be parts of the turbinates.
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The trachea, also called the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends from the larynx and branches into the two primary bronchi. At the top of the trachea the cricoid cartilage attaches it to the larynx. The trachea is formed by a number of horseshoe-shaped rings, joined together vertically by ligaments over their substance and by the trachealis muscle at their ends.
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A rod-like clavicle bone was present along the front edge of each coracoid, and a narrow T-shaped interclavicle was placed between the two coracoids. Possible oval-shaped sternal plates were present behind the pectoral girdle. These plates are bony components of the sternum (breastplate), which in most reptiles is completely cartilaginous and in birds is completely bony. Each humerus (upper arm bone, the only portion of the forelimbs which is completely preserved) is narrow at the mid-shaft but has expanded proximal (near to the body) and distal (away from the body) ends.
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Sharks off Italy also eat small amounts of nematodes, polychaete worms, and other cartilaginous fishes. Studies of velvet bellies off Norway and Portugal, and in the Rockall Trough, have found small sharks under long feed mainly on the krill Meganyctiphanes norvegica and the small fish Maurolicus muelleri. As the sharks grow larger, their diets become more varied, consisting mainly of squid and the shrimp Pasiphaea tarda, as well fishes other than M. muelleri. It has been speculated that smaller velvet bellies may be too slow to catch fast-moving cephalopods.
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A number of other fishes have pronounced bills or beaks, and are sometimes referred to as billfish, despite not being true billfish. Halfbeaks look somewhat like miniature billfish, and the sawfish and sawshark, which are cartilaginous fishes with long, serrated rostrums. Needlefish are sometimes confused with billfish, but they are "easily distinguished from the true billfish by having both jaws prolonged, the dorsal and anal fins both single and similar in size and shape, and the pelvic fins inserted far behind the pectorals." Paddlefish have elongated rostrums containing electroreceptors that can detect weak electrical fields.
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This species feeds on a variety of benthic and pelagic bony fishes, including hake, flounders, rockfishes, lingcod, topsmelt, mackerel, and herring, and on cartilaginous fishes, including elephantfishes (Callorhinchus), spiny dogfish (Squalus acanthias), young bluntnose sixgill sharks (Hexanchus griseus), and ghost catshark (Apristurus) egg cases. Octopuses and squid, including the Humboldt squid (Dosidicus gigas) are also consumed. Young prickly sharks may themselves fall prey to the bluntnose sixgill shark, while adults likely face few threats. Reproduction in this species is aplacental viviparous, with the unborn young sustained by yolk.
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The following five sets are known as "false ribs", three of these sharing a common cartilaginous connection to the sternum, while the last two (eleventh and twelfth ribs) are termed floating ribs. They are attached to the vertebrae only, and not to the sternum or cartilage coming off of the sternum. In general, human ribs increase in length from ribs 1 through 7 and decrease in length again through rib 12. Along with this change in size, the ribs become progressively oblique (slanted) from ribs 1 through 9, then less slanted through rib 12.
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Primitive acanthodians; Mesacanthus pusillus, Parexus falcatus, and Ischnacanthus gracilis Ischnacanthus was first discovered in 1861 by Egerton, and later assigned to Isnacanthidae by A. S. Woodward in 1891. The type specimen that defines this species is named Ischnacanthus gracilis, and helps outline the Ischnacanthidae family it belongs to. Fossils of this fish were first discovered in Tillywhandland Quarry, Forfar, Scotland. The Acanthodians, the class Ischnacanthus is home to, are the subject of some dispute over their systematic position because they have features of both bony fish, the Osteichthyes, and cartilaginous fish, the Chondrichthyes.
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Its lateral border is free and rough, and gives attachment to the cartilaginous part of the ear canal. Internally, the tympanic part is fused with the petrous portion, and appears in the retreating angle between it and the squama, where it lies below and lateral to the orifice of the auditory tube. Posteriorly, it blends with the squama and mastoid part, and forms the anterior boundary of the tympanomastoid fissure. Its upper border fuses laterally with the back of the postglenoid process, while medially it bounds the petrotympanic fissure.
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In the most primitive vertebrates, the hagfishes and lampreys, the cerebrum is a relatively simple structure receiving nerve impulses from the olfactory bulb. In cartilaginous and lobe-finned fishes and also in amphibians, a more complex structure is present, with the cerebrum being divided into three distinct regions. The lowermost (or ventral) region forms the basal nuclei, and contains fibres connecting the rest of the cerebrum to the thalamus. Above this, and forming the lateral part of the cerebrum, is the paleopallium, while the uppermost (or dorsal) part is referred to as the archipallium.
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For example, erythrocytes, macrophages and plasma cells are produced in the anterior kidney (or pronephros) and some areas of the gut (where granulocytes mature.) They resemble primitive bone marrow in hagfish. Cartilaginous fish (sharks and rays) have a more advanced immune system. They have three specialized organs that are unique to chondrichthyes; the epigonal organs (lymphoid tissue similar to mammalian bone) that surround the gonads, the Leydig's organ within the walls of their esophagus, and a spiral valve in their intestine. These organs house typical immune cells (granulocytes, lymphocytes and plasma cells).
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The hatched eggs continue life as tadpoles, which typically have oval bodies and long, vertically flattened tails. As a general rule, free living larvae are fully aquatic. They lack eyelids and have a cartilaginous skeleton, a lateral line system, gills for respiration (external gills at first, internal gills later) and tails with dorsal and ventral folds of skin for swimming. They quickly develop a gill pouch that covers the gills and the front legs; the lungs are also developed at an early stage as an accessory breathing organ.
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Frill-necked lizard showing its neck frills. Skull of Triceratops with its large neck frill. A neck frill is the relatively extensive margin seen on the back of the heads of reptiles with either a bony support such as those present on the skulls of dinosaurs of the suborder Marginocephalia or a cartilaginous one as in the frill-necked lizard. In technical terms, the bone-supported frill is composed of an enlarged parietal bone flanked by elongated squamosals and sometimes ringed by epoccipitals, bony knobs that gave the margin a jagged appearance.
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There is considerable variation in the size and shape of the cerebellum in different vertebrate species. It is generally largest in cartilaginous and bony fish, birds, and mammals, but somewhat smaller in reptiles. The large paired and convoluted lobes found in humans are typical of mammals, but the cerebellum is generally a single median lobe in other groups, and is either smooth or only slightly grooved. In mammals, the neocerebellum is the major part of the cerebellum by mass, but in other vertebrates, it is typically the spinocerebellum.
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Radiation of elasmobranchs, based on Michael Benton, 2005. Elasmobranchii () is a subclass of Chondrichthyes or cartilaginous fish, including the sharks (superorder Selachii) and the rays, skates, and sawfish (superorder Batoidea). Members of this subclass are characterised by having four (tawny nurse sharks have 4 pairs of gills) to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins and small placoid scales on the skin. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper.
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It was described in 1960 by Howard Williams and Peter Campbell. They described a case study of five children with similar clinical and radiological symptoms, and proposed that the abnormal development of cartilage in bronchial tree was responsible for this presentation. In 1976, the first report of the occurrence of familial bronchiectasis in siblings was published, and it supported the theory that WCS was congenital, based on the uniformity of the cartilaginous defect. It may have been the result of an autosomal recessive mutation, but the specific gene has not yet been identified.
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The common ancestor of all present gnathostomes (jawed-vertebrates) lived in freshwater, and later migrated back to the sea. To deal with the much higher salinity in sea water, they evolved the ability to turn the nitrogen waste product ammonia into harmless urea, storing it in the body to give the blood the same osmolarity as the sea water without poisoning the organism. This is the system currently found in cartilaginous fishes. Ray-finned fishes (Actinopterygii) later returned to freshwater and lost this ability, while the fleshy-finned fishes (Sarcopterygii) retained it.
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The facial skeleton is composed of dermal bone and derived from the neural crest cells (also responsible for the development of the neurocranium, teeth and adrenal medulla) or from the sclerotome, which derives from the somite block of the mesoderm. As with the neurocranium, in Chondricthyes and other cartilaginous vertebrates, they are not replaced via endochondral ossification. Variation in craniofacial form between humans is largely due to differing patterns of biological inheritance. Cross-analysis of osteological variables and genome-wide SNPs has identified specific genes that control this craniofacial development.
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The cartilaginous sheaths on their jaws are used for scraping algae and detritus along the gravel and stones within the habitat. An unusual amount of sexual selection has occurred in this species for unknown reasons, and large amounts of energy are expended in male competition and mating success because of this selection. This extra energy is perhaps wasted, and it could be contributing to the decline in fitness and ultimately the disappearance of the species. Populations are declining rapidly in Rucker Canyon along with 'San Bernardino Creek', however numbers in Texas and Mexico remain stable.
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Batoids are flat-bodied, and, like sharks, are cartilaginous marine fish, meaning they have a boneless skeleton made of a tough, elastic cartilage. Most batoids have five ventral slot-like body openings called gill slits that lead from the gills, but the Hexatrygonidae have six. Batoid gill slits lie under the pectoral fins on the underside, whereas a shark's are on the sides of the head. Most batoids have a flat, disk-like body, with the exception of the guitarfishes and sawfishes, while most sharks have a spindle-shaped body.
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Listed as an endangered species, the Virgin River chub is found from Pah Tempe Hot Springs down to Halfway Wash, Nevada. Desert sucker (Catostomus clarkii) State of Utah wildlife species of concern Size: 18″ (46.4 cm) The desert sucker gets its name from the way it feeds on aquatic vegetation and insects. It uses its thick cartilaginous lips to scrape and suck food from rocks and boulders along the bottom of the river. Desert Suckers are very colorful during the spring spawning season, developing bright orange and black 'racing stripes' along their sides.
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The New Zealand eagle ray is a cartilaginous fish with a roughly circular disc-like body, a projecting frog-like head, large fleshy pectoral fins and a long tail armed with a spine that is capable of injecting venom. The pectoral fins beat up and down so that the fish appears to "fly" through the water. This fish can grow to a maximum width of about , with females being rather larger than males. The dorsal surface is olive-green, dark brown or yellowish, with grey or pale blue markings, and the ventral surface is white.
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Compared with Suevoleviathan and Temnodontosaurus, the fluke of Eurhinosaurus was relatively short. The caudal fin of Eurhinosaurus was in hypocercal shape (the notochord extended into the lower lobe) with cartilaginous chevrons which could be used for swimming in a high speed. Life restoration In the vertebral column, the neural spins of the dorsal vertebrae were remarkably short, less than the height of the centrum, which was also found in other lower Jurassic large-bodied ichthyosaur such as Temnodontosaurus and Platypterygius. The forefins of Eurhinosaurus offered a peculiarity: the radius was much larger than the ulna.
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The hatchling shark measures long; males and females begin to mature sexually at and long respectively, corresponding to an age of around 10 years. One source reports the maximum lifespan as at least 15 years, while another source gives at least 19 years. Predators of the leopard catshark include larger sharks and marine mammals; it is one of the cartilaginous fish most often consumed by the broadnose sevengill shark (Notorynchus cepedianus). When threatened, it curls into a ring with its tail covering its head, a behavior also performed by the shysharks (Haploblepharus).
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While the maxilloturbinates of mammals are located in the path of airflow to collect moisture, sensory turbinates in both mammals and reptiles are positioned farther back and above the nasal passage, away from the flow of air. Glanosuchus has ridges positioned low in the nasal cavity, indicating that it had maxilloturbinates that were in the direct path of airflow. The maxilloturbinates may not have been preserved because they were either very thin or cartilaginous. The possibility has also been raised that these ridges are associated with an olfactory epithelium rather than turbinates.
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Teeth are replaced multiple times also in most bony fishes, but unlike cartilaginous fishes, the new tooth erupts only after the old one has fallen out. Jaws probably originated in the pharyngeal arches supporting the gills of jawless fish. The earliest jaws appeared in now extinct placoderms and spiny sharks during the Silurian, about 430 million years ago. The original selective advantage offered by the jaw was probably not related to feeding, but to increased respiration efficiency—the jaws were used in the buccal pump to pump water across the gills.
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The distinctive nasal arch of Gryposaurus, like other cranial modifications in duckbills, may have been used for a variety of social functions, such as identification of sexes or species and social ranking. It could also have functioned as a tool for broadside pushing or butting in social contests, and there may have been inflatable air sacs flanking it for both visual and auditory signaling. The top of the arch is roughened in some specimens, suggesting that it was covered by thick, keratinized skin, or that there was a cartilaginous extension.
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Third, there is also a loss of electroreception in gars, bowfin, and teleosts (neopterygian fishes). Ampullary receptors are present in all surviving cartilaginous fishes and bony fishes except a few species present in Neopterygii (which include gars, bowfins, and teleosts) Fourth, monotremes and a least three groups of fresh-water teleosts re-evolved electroreception. Fifth, a group of teleosts, Xenomystinae, acquired passive electrolocation with low frequency sensitive ampullary receptors. Sixth, another group of teleosts, Mormyroids, evolved passive electrolocation and active location, as well as a pulse type EOD in active electrolocation.
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The fleshy portion of the pomes is developed from the floral tube and like the berry most of the pericarp is fleshy but the endocarp is cartilaginous, an apple is an example of a pome. Lastly, drupes are known for being one seeded with a fleshy mesocarp, an example of this would be the peach. However, there are fruits were the fleshy portion is developed from tissues that are not the ovary, such as in the strawberry. The edible part of the strawberry is formed from the receptacle of the flower.
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Cells from the lateral plate mesoderm and the myotome migrate to the limb field and proliferate to create the limb bud. The lateral plate cells produce the cartilaginous and skeletal portions of the limb while the myotome cells produce the muscle components. The lateral plate mesodermal cells secrete a fibroblast growth factor (FGF7 and FGF10, presumably) to induce the overlying ectoderm to form an important organizing structure called the apical ectodermal ridge (AER).The AER reciprocatively secretes FGF8 and FGF4 which maintains the FGF10 signal and induces proliferation in the mesoderm.
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Fish typically have quite small brains relative to body size compared with other vertebrates, typically one-fifteenth the brain mass of a similarly sized bird or mammal. However, some fish have relatively large brains, most notably mormyrids and sharks, which have brains about as massive relative to body weight as birds and marsupials. The cerebellum of cartilaginous and bony fishes is large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei.
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Conversely, over expression of extracellular MGP effectively abolishes calcification in chondrocytes, suggesting that MGP may function in inhibiting passive calcification in soft tissues. Recent evidence suggests MGP is a vitamin K dependent protein synthesized by chondrocytes and vascular smooth muscle cells, where it potentiates the inhibition of cartilaginous and arterial calcification. Thus, potential vitamin K deficiency, via nutritional deficiency or coumarin-derivative use, would render MGP uncarboxylated and inactive, thus diminishing biological function. Arterial calcification resulting from MGP inactivation results in inimical prognosis, commonly seen in patients with diabetes, atherosclerosis, and renal dysfunction.
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This is connected indirectly with the eardrum via a mostly cartilaginous extracolumella and medially to the inner-ear spaces via a widened footplate in the fenestra ovalis. The columella is an evolutionary derivative of the bone known as the hyomandibula in fish ancestors, a bone that supported the skull and braincase. The structure of the middle ear in living amphibians varies considerably and is often degenerate. In most frogs and toads, it is similar to that of reptiles, but in other amphibians, the middle ear cavity is often absent.
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The TMEM39B gene appears most distantly in cartilaginous fish (chondrichthyes), which diverged from humans approximately 465 million years ago.Kumar S, Stecher G, Suleski M, Hedges SB (2017) TimeTree: A Resource for Timelines, Timetrees, and Divergence Times. Mol Biol Evol doi:10.1093/molbev/msx116 Orthologs of the paralog TMEM39A are found in arthropods, which diverged from humans approximately 763 million years ago, suggesting that TMEM39B was produced by the duplication of an ancestral form of TMEM39A . TMEM39B evolves at a relatively slow rate; a 1% change in the amino acid sequence requires approximately 13.9 million years.
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Cuban solenodon at New York Zoo Skull of Solenodon paradoxus Traditionally, Solenodons' closest relatives were considered to be the giant water shrew of Africa and Tenrecidae of Madagascar, though they are now known to be more closely related to true shrews (Eulipotyphla). Solenodons resemble very large shrews, and are often compared to them; with extremely elongated cartilaginous snouts, long, naked, scaly tails, hairless feet, and small eyes. The Cuban solenodon is generally smaller than its Hispaniolan counterpart. It is also a rusty brown with black on its throat and back.
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This suggests that TMEM151B is likely found in many cartilaginous fishes; it is simply not recorded. TMEM151B could not be found in jawless fish in either BLAST or BLAT. This table shows a list of TMEM151 orthologues in 28 species. The table demonstrates whether TMEM151A or TMEM151B is found in the animal, the name of the species as well as its clade, the percent identity of the orthologue to humans, how many millions of years ago the species diverged from humans, and the NCBI accession code for the orthologue.
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Illustration of Limnoscelis left foreleg from The Osteology of the Reptiles (1925) The pectoral girdle of Limnoscelis consisted of a single interclavicle, with paired clavicles, scapulocoracoids, and cleithra on its right and left sides. The cleithrum was small and possibly vestigial, indicating further ossification of the scapulocoracoid. Limnoscelis may also have had cartilaginous extensions above the scapolocoracoid, compensating for this reduction in size. The scapulocoracoid of Limnoscelis had two fused coracoid elements, which it shares with a number of basal amniotes, but which differentiates Limnoscelis from its fellow diadectomorphs (which only had a single coracoid).
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The general structure of teeth is similar across the vertebrates, although there is considerable variation in their form and position. The teeth of mammals have deep roots, and this pattern is also found in some fish, and in crocodilians. In most teleost fish, however, the teeth are attached to the outer surface of the bone, while in lizards they are attached to the inner surface of the jaw by one side. In cartilaginous fish, such as sharks, the teeth are attached by tough ligaments to the hoops of cartilage that form the jaw.
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River stingrays or freshwater stingrays are Neotropical freshwater fishes of the family Potamotrygonidae in the order Myliobatiformes, one of the four orders of batoids, cartilaginous fishes related to sharks. They are found in rivers in tropical and subtropical South America (freshwater stingrays in Africa, Asia and Australia are in another family, Dasyatidae). A single marine genus, Styracura, of the tropical West Atlantic and East Pacific are also part of Potamotrygonidae. They are generally brownish, greyish or black, often with a mottled, speckled or spotted pattern, have disc widths ranging from and venomous tail stingers.
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For example, erythrocytes, macrophages and plasma cells are produced in the anterior kidney (or pronephros) and some areas of the gut (where granulocytes mature.) They resemble primitive bone marrow in hagfish. Cartilaginous fish (sharks and rays) have a more advanced immune system. They have three specialized organs that are unique to Chondrichthyes; the epigonal organs (lymphoid tissue similar to mammalian bone) that surround the gonads, the Leydig's organ within the walls of their esophagus, and a spiral valve in their intestine. These organs house typical immune cells (granulocytes, lymphocytes and plasma cells).
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The skeleton is somewhat typical of tetrapods, although the skull, pelvis and ribs are specialised; in particular, the cartilaginous processes of the ribs allow the thorax to collapse during diving and the structure of the pelvis can accommodate large masses of food, or more air in the lungs. Both sexes have a cloaca, a single chamber and outlet at the base of the tail into which the intestinal, urinary and genital tracts open. It houses the penis in males and the clitoris in females.Grigg and Gans, p. 336.
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Lily-like crinoids (animals, their resemblance to flowers notwithstanding) were abundant, and trilobites were still fairly common. Among vertebrates, jawless armored fish (ostracoderms) declined in diversity, while the jawed fish (gnathostomes) simultaneously increased in both the sea and fresh water. Armored placoderms were numerous during the lower stages of the Devonian Period and became extinct in the Late Devonian, perhaps because of competition for food against the other fish species. Early cartilaginous (Chondrichthyes) and bony fishes (Osteichthyes) also become diverse and played a large role within the Devonian seas.
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A single cartilaginous tubercle is present at the mantle margins, though rarely it may be absent. The fins are long and narrow, starting at about 40 to 60% of the length of the mantle, far from where the body is the widest. They extend past the rear tip of the body, fuse with each other at the middle, and end with a pair of small lobes. arms and buccal (mouth) cavity; arm suckers; gladius; tentacle; and tentacular suckers The arms are short to medium length, about a fourth to half of the mantle length.
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The bony fish have three pairs of arches, cartilaginous fish have five to seven pairs, while the primitive jawless fish have seven. The vertebrate ancestor no doubt had more arches, as some of their chordate relatives have more than 50 pairs of gills. Gills usually consist of thin filaments of tissue, branches, or slender tufted processes that have a highly folded surface to increase surface area. The high surface area is crucial to the gas exchange of aquatic organisms as water contains only a small fraction of the dissolved oxygen that air does.
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Following the devastation of a bushfire, echidnas can compensate for the lack of food by reducing their daytime body temperature and activity through use of torpor, for a period of up to three weeks. The echidna's optical system is an uncommon hybrid of both mammalian and reptilian characteristics. The cartilaginous layer beneath the sclera of the eyeball is similar to that of reptiles and avians. The small corneal surface is keratinised and hardened, possibly to protect it from chemicals secreted by prey insects or self-impalement when it rolls itself up, which has been observed.
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Stingrays are a group of sea rays, which are cartilaginous fish related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae (deepwater stingray), Urolophidae (stingarees), Urotrygonidae (round rays), Dasyatidae (whiptail stingrays), Potamotrygonidae (river stingrays), Gymnuridae (butterfly rays), and Myliobatidae (eagle rays). Stingrays are common in coastal tropical and subtropical marine waters throughout the world. Some species, such as Dasyatis thetidis, are found in warmer temperate oceans, and others, such as Plesiobatis daviesi, are found in the deep ocean.
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Evidence for this includes the isometric growth pattern exhibited by S, M, and P elements. If the conodont animal relied upon a filter feeding strategy then this growth pattern would not provide the necessary surface area needed to support ciliated tissue as the animal grew. In more recent findings, researchers have also identified cartilaginous structures similar to those present in modern hagfish and lampreys which are predatory/scavengers. It is possible that multiple feeding strategies may have arisen in different groups of conodonts as they are a diverse clade.
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The splitfin flashlightfish is characterized by two bean shaped torch-like organs under its eyes containing bioluminescent bacteria, which the fish can turn on and off by blinking. The light organs are embedded in suborbital cavities and are connected at the anterior edge via a cartilaginous rod like attachment. The suborbital light organs are densely settled with luminous symbiotic bacteria that grow in tubular structures and produce a constant bluish light.Hellinger, Jens, Peter Jägers, Marcel Donner, Franziska Sutt, Melanie D. Mark, Budiono Senen, Ralph Tollrian, and Stefan Herlitze.
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In 2016 a morphological study showed that Tullimonstrum may have been a basal vertebrate, and thus a member of the phylum Chordata, with one study suggesting Tullimonstrum may be closely related to modern lampreys. This affinity was attributed based on pronounced cartilaginous arcualia, a dorsal fin and asymmetric caudal fin, keratinous teeth, a single nostril, and tectal cartilages like in lampreys. McCoy et al. raised the possibility that Tullimonstrum belongs to the ancestral group of lamprey, but it also has many features not found in Cyclostomes (lampreys and hagfishes).
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Sturgeon skull – a, Rostrum; b, nasal capsule; c eye-socket; d, foramina for spinal nerves; e, notochord; g, quadrate bone; h, hyomandibular bone; i, mandible; j. basibranchials; k, ribs; l, hyoid bone; I, II, III, IV, V, branchial arches Sturgeons retain several primitive characters among the bony fishes. Along with other members of the subclass Chondrostei, they are unique among bony fishes because their skeletons are almost entirely cartilaginous. Notably, however, the cartilagineous skeleton is not a primitive character, but a derived one; sturgeon ancestors had bony skeletons.
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Tonic immobility has been reported in several cartilaginous fishes, one of which is M. canis. Tonic immobility is induced by grasping the first dorsal fin with one hand and the body immediately anterior to the anal fin with the other, inverting the shark and holding it rigidly. The mean time to induce tonic immobility in smooth dogfish was 32.5 seconds. The mean duration of the tonic immobility was 61.9 seconds. Sharks that had the “limp” response also exhibited tonic immobility. The “limp” response is a criterion for the onset of tonic immobility.
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A tendon that runs through cartilaginous rings attached to the phalange allow an automatic locking system. The weigh tof the bat keeps the tendon taught, and hence the toes gripping when hanging, so the bat may sleep without falling from its roost. The uropatagium, the flap of skin that extends between the back legs and tail is supported by the calcaneum bone, which is located near the ankle. The forelimb bones are all elongated, with the degree of elongation increasing the farther the bones are from the body.
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The Antarctic toothfish has a lightweight, partially cartilaginous skeleton, lacks a swim bladder, and has fatty deposits which act as a stored energy source, particularly during spawning. This fat also makes large toothfish neutrally buoyant. Many toothfish caught over the seamounts are very depleted of fat, and this is thought perhaps to be related to spawning and spawning migration, which are energy-demanding activities.Fenaughty, J.M.; Eastman, J.T.; and Sidell, B.D. (2008). Biological implications of low condition factor “axe handle” specimens of the Antarctic toothfish, Dissostichus mawsoni, from the Ross Sea.
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Aspirin has been shown to have three additional modes of action. It uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria, by diffusing from the intermembrane space as a proton carrier back into the mitochondrial matrix, where it ionizes once again to release protons. In short, aspirin buffers and transports the protons, acting as a competitor to ATP synthase. When high doses of aspirin are given, aspirin may actually cause hyperthermia due to the heat released from the electron transport chain, as opposed to the antipyretic action of aspirin seen with lower doses.
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Cretalamna (13, lower right) with contemporaneous aquatic animals Fossil evidence of Cretalamna is found in deposits representing a diverse set of marine environments, indicating that it was able to adapt to a wide range of habitats. This may have attributed to its ability to exist through a long temporal range. The fusiform body of Cretalamna suggests it was a pelagic shark. The Cretaceous waters inhabited by Cretalamna were also home to a diverse range of cartilaginous fishes, bony fishes, turtles, squamates, plesiosaurs, pterosaurs, birds, and even some non-avian dinosaurs.
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Cephalopods have the most highly developed nervous systems among invertebrates. Squids have a complex brain in the form of a nerve ring encircling the oesophagus, enclosed in a cartilaginous cranium. Paired cerebral ganglia above the oesophagus receive sensory information from the eyes and statocysts, and further ganglia below control the muscles of the mouth, foot, mantle and viscera. Giant axons up to in diameter convey nerve messages with great rapidity to the circular muscles of the mantle wall, allowing a synchronous, powerful contraction and maximum speed in the jet propulsion system.
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This terminology persists in referring to endospermic seeds as "albuminous". The nature of this material is used in both describing and classifying seeds, in addition to the embryo to endosperm size ratio. The endosperm may be considered to be farinaceous (or mealy) in which the cells are filled with starch, as for instance cereal grains, or not (non-farinaceous). The endosperm may also be referred to as "fleshy" or "cartilaginous" with thicker soft cells such as coconut, but may also be oily as in Ricinus (castor oil), Croton and Poppy.
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Felicia wrightii is a perennial plant, herbaceous plant, of up to high. Its leaf rosettes usually develop several, up to about long runners, at the end of which daughter rosettes appear. Most leaves are in a rosette, but smaller ones sit alternately on the stalk. The rosette leaves are elliptic to inverted egg- shaped, up to 4 cm (1 in) long and 1 cm ( in) wide, with an indistinctly pointed tip, and the surface hairless or quickly becoming so, while the leaf margins are cartilaginous and set with tough bristles.
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The following outline is provided as an overview of and topical guide to fish: Fish – any member of a paraphyletic group of organisms that consist of all gill-bearing aquatic craniate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups. Most fish are ectothermic ("cold-blooded"), allowing their body temperatures to vary as ambient temperatures change, though some of the large active swimmers like white shark and tuna can hold a higher core temperature. Fish are abundant in most bodies of water.
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The flying membrane stretched from wrist to ankle and was supported by a cartilaginous strip which had its origin at the elbow. (The east Asian flying squirrels have a similar cartilage strip, but it terminates at the wrist.) The scaly tailed squirrels had an additional membrane extending from the ankle to part-way along the tail, and when extended, the membrane formed a straight line from heel to heel. Ten years later, a specimen of another species, Pel's flying squirrel, was brought to Europe and showed similar anatomical features. The hands and feet had the digits close together with strongly curved nails.
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The internasal wall of the rostral plate connects the ventral, anterior, and dorsal walls in order to divide the nasal sacs which are relatively small. The nasal sacs are bound between the rostral plate and the rhinocapsular section of the cartilaginous endocranium and are placed some distance from the telencephalon and opened antero-dorsally. They are located posterior to the nares which were located in the anterior part of the nasal sacs. The structure of the orbito-nasal cavity in the Asterolepis ornata has been studied, providing a detailed description of the premedian, rostral, and pineal plates, and bones of the sclerotic ring.
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John Samuel Budgett (16 June 1872 – 19 January 1904) was a British zoologist and embryologist. He spent most of his short career on the genus Polypterus (bichir). This is found in the lakes, river margins, swamps, and floodplains of tropical central and western Africa and the Nile River system. Zoologists at the time wondered whether it was a bony fish, a cartilaginous fish, a lungfish or a primitive amphibian. Forty years after the publication of Darwin’s Origin of Species, zoologists were seeking to map the history of species and this primitive animal was a key part of the map.
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It was initially expected that J chain would be important for forming the polymeric immunoglobulins, and indeed polymerization of IgA depends strongly (but not absolutely) on J chain. In contrast, polymeric IgM forms efficiently in the absence of J chain. The predominant form of human and mouse IgM is pentamer. By way of comparison, IgM from frog (Xenopus) is predominantly hexamer, IgM from bony fish is predominantly tetramer, and IgM from cartilaginous fish (shark) is predominantly pentamer. The predominance of pentamer in mouse and human IgM notwithstanding, it was evident that these IgM’s could also exist as hexamer.
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The floor of the nose is made up of the incisive bone and the horizontal plates of the palatine bones, and this makes up the hard palate of the roof of the mouth. The two horizontal plates join together at the midline and form the posterior nasal spine that gives attachment to the musculus uvulae in the uvula. The two maxilla bones join at the base of the nose at the lower nasal midline between the nostrils, and at the top of the philtrum to form the anterior nasal spine. This thin projection of bone holds the cartilaginous center of the nose.
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George Montagu's introduction, "in hopes of advancing knowledge of the subject",Montagu, 1802. p. i mentions Thomas Pennant as being "diffuse on the subject" of ornithology, as well as Dr. Latham's General Synopsis of Birds and his Index Ornithologicus.Montagu, 1802. p. ii He then introduces the anatomy of birds, separating those with a cartilaginous stomach or gizzard, and those with a membranous stomach; those that incubate their young, and the cuckoo that does not; with remarks on instincts such as carrying shell fragments away from the nest, birdsong, and feet adapted for different purposes, such as climbing or swimming.
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When this pressure exceeds the elasticity of the tissues, they burst; thus the membranous part of the trachea is more commonly affected by this mechanism of injury than cartilaginous portions. The second mechanism may occur when the chest is suddenly decelerated, as occurs in vehicle accidents, producing a shearing force. The lungs are mobile in the chest cavity but their movement is more restricted near the hilum. Areas near the cricoid cartilage and carina are fixed to the thyroid cartilage and the pericardium respectively; thus if the airways move, they can tear at these points of fixation.
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Comorian waters are the habitat of the coelacanth, a rare fish with limblike fins and a cartilaginous skeleton, the fossil remains of which date as far back as 400 million years and which was once thought to have become extinct about 70 million years ago. A live specimen was caught in 1938 off southern Africa; other coelacanths have since been found in the vicinity of the Comoro Islands. Several mammals are unique to the islands themselves. Livingstone's fruit bat, although plentiful when discovered by explorer David Livingstone in 1863, has been reduced to a population of about 120, entirely on Anjouan.
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Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used for extinct members of the subclass Elasmobranchii outside the Selachimorpha, such as Cladoselache and Xenacanthus, as well as other Chondrichthyes such as the holocephalid eugenedontidans. Under this broader definition, the earliest known sharks date back to more than 420 million years ago.
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As clearly seen in the lamprey, Cyclostome also has a pair of cartilaginous rods in the embryonic head which is similar to the trabecular cartilages in jawed vertebrates. However, in 1916, Alexej Nikolajevich Sewertzoff pointed out that the cranial base of the lamprey is exclusively originated from the paraxial mesoderm. Then in 1948, Alf Johnels reported the detail of the skeletogenesis of the lamprey, and showed that the “trabecular cartilages” in lamprey appear just beside the notochord, in a similar position to the parachordal cartilages in jawed vertebrates.Johnels AG (1948) On the development and morphology of the skeleton of the head of Petromyzon.
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The sacral ribs were stout and short, since they formed part of the pelvis, connecting the backbone to the hip bones. In most subsequent forms, many of these early ribs have been lost, and in living amphibians and reptiles, there is great variation in rib structure and number. For example, turtles have only eight pairs of ribs, which are developed into a bony or cartilaginous carapace and plastron, while snakes have numerous ribs running along the full length of their trunk. Frogs typically have no ribs, aside from a sacral pair, which form part of the pelvis.
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They are rather difficult to observe, since the shell (when present) is mostly colorless, very fragile and usually less than 1 cm in length. Although their shell may be so fine as to be transparent, it is nevertheless calcareous; their shells are bilaterally symmetric and can vary widely in shape: coiled, needle-like, triangular, globulous. The shell is present in all stages of the Cavolinioidea (euthecosomata) life cycle, whereas in the Cymbulioidea (pseudothecosomata), adult Peraclididae bear shells, Cymbuliidae shed their larval shells and develop a cartilaginous pseudoconch in adulthood, and Desmopteridaen adults lack any rigid structure.
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Indeed, in many cartilaginous fish, the anterior portion of the kidney may degenerate or cease to function altogether in the adult. In the most primitive vertebrates, the hagfish and lampreys, the kidney is unusually simple: it consists of a row of nephrons, each emptying directly into the archinephric duct. Invertebrates may possess excretory organs that are sometimes referred to as "kidneys", but, even in Amphioxus, these are never homologous with the kidneys of vertebrates, and are more accurately referred to by other names, such as nephridia. In amphibians, kidneys and the urinary bladder harbour specialized parasites, monogeneans of the family Polystomatidae.
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Like other members of Acipenseriformes the skeleton was cartilaginous and the body was smooth and largely lacking in scales, except for small scales in the caudal peduncle and caudal fin. They reached sexual maturity at a weight of around , usually by the time they were age seven or eight, with a typical body length of . Anecdotal reports indicate the Chinese paddlefish could reach in length and weigh up to , or even several thousand pounds. Limited research has been conducted on the species maximum size and weight as a result of its endangered status and lack of sightings over the years.
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Retrieved 4 December 2014. In early fish and in chondrichthyans (cartilaginous fish such as sharks), the Meckelian Cartilage continued to be the main component of the lower jaw. But in the adult forms of osteichthyans (bony fish) and their descendants (amphibians, reptiles(including birds), mammals), the cartilage was covered in bone – although in their embryos the jaw initially develops as the Meckelian Cartilage. In all tetrapods the cartilage partially ossifies (changes to bone) at the rear end of the jaw and becomes the articular bone, which forms part of the jaw joint in all tetrapods except mammals.
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The use of the neck frill in dinosaurs is uncertain; it may have been used for thermoregulation or simply as a defense mechanism. Indeed, during battles for territory, competing Triceratops crashed heads together with their elongated horns and the neck frill may have been employed as a kind of shield, protecting the rest of the animal from harm. However, usage of the neck frill in modern reptiles is better documented. Two chief and disparate examples are the horned lizards (genus Phrynosoma) with a bony frill, and the frill-necked lizard (genus Chlamydosaurus) with a cartilaginous frill.
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The frill-necked lizard's frill is mainly made up of flaps of skin, which are usually coloured pink, supported by cartilaginous spines. Similar to the portrayal of the dinosaur Dilophosaurus in Steven Spielberg's Jurassic Park, frill-necked lizard puff out these neck frills on either side of its head when threatened. The lizards often raise their frills when battling for territory or when coming into contact with another lizard, especially during mating season. There is, however, no evidence that suggests that Dilophosaurus had the same abilities, as many of its features in the Jurassic Park film were mostly fictional.
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A large species reaching long, the copper shark is difficult to distinguish from other large requiem sharks. It is characterized by its narrow, hook-shaped upper teeth, lack of a prominent ridge between the dorsal fins, and plain bronze coloration. Feeding mainly on cephalopods, bony fishes, and other cartilaginous fishes, the copper shark is a fast-swimming predator that has been known to hunt in large groups, utilizing their numbers to their advantage; however for most of the time they remain solitary. Off South Africa, this species associates closely with the annual sardine run, involving millions of southern African pilchard (Sardinops sagax).
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Placoderm. Early armoured fish did not have a skull in the common understanding of the word, but had an endocranium that was partially open above, topped by dermal bones forming armour. The dermal bones gradually evolved into a fixed unit overlaying the endocranium like a heavy "lid", protecting the animal's head and brain from above. Cartilaginous fish whose skeleton is formed from cartilage lack a continuous dermal armour and thus have no proper skull roof. A more or less full shield of fused dermal bones was common in early bony fishes of the Devonian, and particularly well developed in shallow water species.
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The roof of each nasal cavity is formed in its upper third to one half by the nasal bone and more inferiorly by the junctions of the upper lateral cartilage and nasal septum. Connective tissue and skin cover the bony and cartilaginous components of the nasal dorsum. The floor of the nasal cavities, which also form the roof of the mouth, is made up by the bones of the hard palate: the horizontal plate of the palatine bone posteriorly and the palatine process of the maxilla anteriorly. The most anterior part of the nasal cavity is the nasal vestibule.
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Three-toed feet of Iguanodon Ornithopoda means "bird feet", from the Greek ornithos ("bird") and pous ("feet"); this refers to their characteristic three-toed feet, although many early forms retained four toes. They were also characterized by having no armour, the development of a horny beak, an elongated pubis that eventually extended past the ilium, and a missing hole in the lower jaw, called a Mandibular fenestrae. A variety of ornithopods and related cerapods had thin cartilaginous plates along the outside of the ribs; in some cases, these plates mineralized and were fossilized. The function of these intercostal plates is unknown.
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Most chondroitin appears to be made from extracts of cartilaginous cow and pig tissues (cow trachea and pig ear and nose), but other sources such as shark, fish, and bird cartilage are also used. Since chondroitin is not a uniform substance, and is naturally present in a wide variety of forms, the precise composition of each supplement will vary. In fact, although many food supplement companies produce their products in compliance with human food processing Good Manufacturing Practice (GMP), most of them do not produce their products in compliance with the GMP regulations for pharmaceuticals, resulting in products not meeting pharmaceutical requirements.
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Work in the early 2000s has challenged the Weishampel model. A study published in 2008 by Casey Holliday and Lawrence Witmer found that ornithopods like Edmontosaurus lacked the types of skull joints seen in those modern animals that are known to have kinetic skulls (skulls that permit motion between their constituent bones), such as squamates and birds. They proposed that joints that had been interpreted as permitting movement in dinosaur skulls were actually cartilaginous growth zones. An important piece of evidence for Weishampel's model is the orientation of scratches on the teeth, showing the direction of jaw action.
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Mastigopsis hjorti is similar to Idioteuthis cordiformis in that it has large fins, skin tubercles, no pocket between the bridles and the large dividing, protective membranes on the tentacular clubs but the main difference is that this species has photophores on its eyes. The suckers on the tentacular club are all of similar size, except for those nearest the tip. The funnel has a locking-apparatus which has an oval, slightly curved depression and towards the posterior its sides protrude having no cartilaginous fleshy projections. The fins are large and measure around 90% of the length of the mantle.
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Skates (hongeo) are cartilaginous fish that excrete uric acid through the skin, rather than by urinating as other animals do. As they ferment, ammonia is produced which helps preserve the flesh and gives the fish its distinctive, powerful odor. The natural preservative effect of the fermentation process on skate meat was noted by Korean fishermen as early as the 14th century, during the Goryeo dynasty, long before refrigeration was invented. It was found that skates were the only fish that could be transported over long distances or stored for extended periods without rotting, even in the absence of salt.
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The premaxilla is covered in grooves and ridges, making it the most ornamented bone from the entire fossil. At the anterior end the premaxillae come together in a short triangular projection pointing ventrally and in another pointing dorsally. These would have been connected by a cartilaginous septum separating the two external nares, although this has not been preserved. The premaxilla bears two incisiform teeth and one caniniform tooth; this has led some to place it in the sphagesaurid group of crocodyliforms, since these also had differentiated teeth, although as the cladogram below suggests this is disputed.
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Osteochondromas have a low rate of malignancy (<1%) and resection of the tumor is suggested if symptoms such as pain, limitation of movement, or impingement on nerves or vessels occur. Resection of the tumor also takes place when the tumor increases in size and progresses towards malignancy. During surgical resection, the entire lesion along with the cartilaginous cap should be removed to minimize any chances of reoccurrences. Surgical treatment becomes the sole treatment of choice if common complications such as fractures, symptoms of peripheral nerves such as paresthesia, paraplegia, peroneal neuropathy, and upper limb neuropathy take place.
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The Florida softshell turtle is a large turtle with a flattened, pancake-like body, a long neck, an elongated head with a long snorkel-like nose, and large webbed feet, each with three claws. While most turtles have hard shells composed of scutes, the Florida softshell has a cartilaginous carapace covered in leathery skin. Ranging from olive green to dark brown, it has the darkest coloration of all the softshell species that inhabit Florida (other species include Apalone mutica calvata and Apalone spinifera aspera). It is also characterized by a white or cream-colored underside.Apalone. www.tortoise.
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However, subsequent analyses have cast doubt on this assessment, instead proposing that the two preserved proximal tarsals are the fibulare and intermedium, and that Limnoscelis possessed an unfused tibiale along with these elements. The absence of the tibiale has been attributed either to poor preservation (possibly due to being cartilaginous), or to being displaced and misidentified as one of the distal tarsals. This differs from other diadectomorphs in the family Diadectidae, which possessed an astragalus consisting of a fused tibiale, intermedium, and proximal centrale, similar (and possibly homologous) to the astragalus or talus bone found in amniotes.
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370 BC) condemned the practice of tracheotomy. Warning against the unacceptable risk of death from inadvertent laceration of the carotid artery during tracheotomy, Hippocrates also cautioned that "The most difficult fistulas are those that occur in the cartilaginous areas." Homerus of Byzantium is said to have written of Alexander the Great (356–323 BC) saving a soldier from asphyxiation by making an incision with the tip of his sword in the man's trachea. Despite the concerns of Hippocrates, Galen of Pergamon (129–199) and Aretaeus of Cappadocia (both of whom lived in Rome in the 2nd century AD) credit Asclepiades of Bithynia (ca.
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In 1989, Emily B. Griffin found that Stegoceras and other pachycephalosaurs had a good sense of smell (olfaction), based on the study of cranial endocasts that showed large olfactory bulbs in the brain. In 2014, Jason M. Bourke and colleagues found that Stegoceras would have needed cartilaginous nasal turbinates in the front of the nasal passages for airflow to reach the olfactory region. Evidence for the presence of this structure is a bony ridge to which it could have attached. The size of the olfactory region also indicates that Stegoceras had a keen sense of smell.
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In modern times, brachiopods are not as common as bivalves. Both groups have a shell consisting of two valves, but the organization of the shell is quite different in the two groups. In brachiopods, the two valves are positioned on the dorsal and ventral surfaces of the body, while in bivalves, the valves are on the left and right sides of the body, and are, in most cases, mirror images of one other. Brachiopods have a lophophore, a coiled, rigid cartilaginous internal apparatus adapted for filter feeding, a feature shared with two other major groups of marine invertebrates, the bryozoans and the phoronids.
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Only placentals, and possibly the early mammaliformes Megazostrodon and Erythrotherium, lack them;Jason A. Lillegraven, Zofia Kielan-Jaworowska, William A. Clemens, Mesozoic Mammals: The First Two-Thirds of Mammalian History, University of California Press, 17/12/1979 - 321 in thylacines and sparassodonts, they appear to have become primarily cartilaginous and the osseous element has become strongly reduced or even absent.Marshall, L. Evolution of the Borhyaenidae, extinct South American predaceous marsupials. Berkeley: University of California Press, 1978.naturalworlds.org Trichosurus mimicked placentals in shifting hypaxial muscles attachment sites from the epipubic to the pelvis, losing the respiratory benefits (see below), but otherwise retains large epipubics.
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The upper tube is formed from the vertebral arches, but also includes additional cartilaginous structures filling in the gaps between the vertebrae, enclosing the spinal cord in an essentially continuous sheath. The lower tube surrounds the notochord and has a complex structure, often including multiple layers of calcification. Lampreys have vertebral arches, but nothing resembling the vertebral bodies found in all higher vertebrates. Even the arches are discontinuous, consisting of separate pieces of arch- shaped cartilage around the spinal cord in most parts of the body, changing to long strips of cartilage above and below in the tail region.
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Apart from some particularly large dermal bones that form parts of the skull, these scales are lost in tetrapods, although many reptiles do have scales of a different kind, as do pangolins. Cartilaginous fish have numerous tooth-like denticles embedded in their skin in place of true scales. Sweat glands and sebaceous glands are both unique to mammals, but other types of skin glands are found in fish. Fish typically have numerous individual mucus-secreting skin cells that aid in insulation and protection, but may also have venom glands, photophores, or cells that produce a more watery serous fluid.
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Sauroposeidon also shared its paleoenvironment with other dinosaurs, such as the sauropod Astrodon (Pleurocoelus) and the most common dinosaur in this region, the ornithopod Tenontosaurus. Other vertebrates present during this time included the amphibian Albanerpeton arthridion, the reptiles Atokasaurus metarsiodon and Ptilotodon wilsoni, the cartilaginous fish Hybodus buderi and Lissodus anitae, the ray-finned fish Gyronchus dumblei, the crocodilians Goniopholis, Bernissartia, and Paluxysuchus, and the turtles Glyptops and Naomichelys. Possible indeterminate bird remains are also known from the Antlers Formation. The fossil evidence suggests that the gar Lepisosteus was the most common vertebrate in this region.
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The upper tube is formed from the vertebral arches, but also includes additional cartilaginous structures filling in the gaps between the vertebrae, and so enclosing the spinal cord in an essentially continuous sheath. The lower tube surrounds the notochord, and has a complex structure, often including multiple layers of calcification. Lampreys have vertebral arches, but nothing resembling the vertebral bodies found in all higher vertebrates. Even the arches are discontinuous, consisting of separate pieces of arch-shaped cartilage around the spinal cord in most parts of the body, changing to long strips of cartilage above and below in the tail region.
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Located at the University of Kentucky, the AGSC is dedicated to supplying genetically well-characterized axolotl embryos, larvae, and adults to laboratories throughout the United States and abroad. An NIH-funded NCRR grant has led to the establishment of the Ambystoma EST database, the Salamander Genome Project (SGP) that has led to the creation of the first amphibian gene map and several annotated molecular data bases, and the creation of the research community web portal. Anurans can only regenerate their limbs during embryonic development. Once the limb skeleton has developed regeneration does not occur (Xenopus can grow a cartilaginous spike after amputation).
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The exterior may be smooth or roughened, with a wing or raphe (ridge), aril or one to two tails, rarely hairy, but may be dull or shiny and the lack of a black integument distinguishes them from related taxa such as Allioideae that were previously included in this family, and striate (parallel longitudinally ridged) in the Steptopoideae. The hilum (scar) is generally inconspicuous. The bitegmic (separate testa and tegmen) seed coat itself may be thin, suberose (like cork), or crustaceous (hard or brittle). The endosperm is abundant, cartilaginous (fleshy) or horny and contains oils and aleurone but not starch (non-farinaceous).
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Phaeocollybia is defined as mushrooms, with a glutinous or moist or sometimes dry and innately scaly, conic, umbonate cap, a rooting, cartilaginous to wiry stipe, generally lacking a visible veil or cortina or with faint traces, and spores which are brown in deposit. The spores are ornamented but will lack a germ pore or plage. The most distinctive feature microscopically is the presence of tibiiformIn the shape of a tibia bone, that is, with a long narrow neck with an apex that is swollen into a knob, like a tibia. cystidia or branches on the mycelium and mycorrhizal sheaths.
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The lake sturgeon (Acipenser fulvescens), also known as the rock sturgeon, is a North American temperate freshwater fish, one of about 25 species of sturgeon. Like other sturgeons, this species is an evolutionarily ancient bottom feeder with a partly cartilaginous skeleton, an overall streamlined shape and skin bearing rows of bony plates on its sides and back, resembling an armored torpedo. The fish uses its elongated, spade-like snout to stir up the substrate and sediments on the beds of rivers and lakes while feeding. The lake sturgeon has four purely sensory organs that dangle near its mouth.
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The shiny and dark green leaves are scattered along the branchlets and often also covered with hairs, especially on younger twigs. They vary in size and shape, but are usually widest above the middle with a rather abruptly narrowed apex, similar to many Myrtaceae. The raised and somewhat cartilaginous ring of the corolla throat is reminiscent of that of species of Prestonia (Apocynaceae) from the same geographic region; it probably reflects adaptation to pollinator foraging behaviour. Nothing is known directly of the pollinators, but the floral features described above are shared by other South American brunfelsias for which butterfly pollination has been observed.
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Primula lutea is a species of primrose that grows on basic rocks in the mountain ranges of southeastern Europe, including the southern and eastern Alps, southern Carpathians, Apennines, and the Balkans. The leaves are obovate and stalkless, with a cartilaginous edge, all growing in a basal rosette. The yellow flowers grow in clusters on 5–20 cm long stalks. In the past it was considered synonymous with the very similar Primula auricula, but a recent study split this species off from P. auricula, with the latter being found in the more northerly areas (western Alps, Jura, Vosges, Black Forest and Tatra mountains).
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Myledaphus is a genus of Late Cretaceous cartilaginous fish whose fossils are known from Canada, the Midwest of the United States, Olmos Formation of the Difunta Group of Mexico, and the Beshtyubin and Bissekty Formations of Uzbekistan. It was a freshwater guitarfish that probably reached a length of , and had teeth adapted for a durophagous diet of animals such as clams. Most taxonomic authories place the genus in the Rhinobatidae, with a few placing it with prehistoric sharks (Anacoracidae), although the latter may be incorrect. Two species are known: Myledaphus bipartitus, the type species, and Myledaphus araucanus, named in 2019.
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The common base of the flowers in the same head is flattened globe-shaped and at only about 2 mm across comparatively very small. The bracts that subtend the head are set in a single whorl, each lance-shaped with a pointy tip, about 6 mm (¼ in) long and 1½–2 mm (0.06–0.08 in) wide. The bract that subtends each flower individually is lance-shaped to broadly oval, with a pointy tip, somewhat cartilaginous in consistency, covered with a thick layer of felty hairs, growing to approximately 1 cm long and becoming woody after the flower has been pollinated.
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Another less general type of magnetic sensing mechanism in animals that has been described is electromagnetic induction used by sharks, stingrays and chimaeras (cartilaginous fish). These species possess a unique electroreceptive organ known as ampullae of Lorenzini which can detect a slight variation in electric potential. These organs are made up of mucus-filled canals that connect from the skin's pores to small sacs within the animal's flesh that are also filled with mucus. The ampullae of Lorenzini are capable of detecting DC currents and have been proposed to be used in the sensing of the weak electric fields of prey and predators.
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Whether it is considered to be a subfield of paleontology, paleozoology, or paleobiology, this discipline is the scientific study of prehistoric invertebrates by analyzing invertebrate fossils in the geologic record. By invertebrates are meant the non-vertebrate creatures of the kingdom Animalia (or Metazoa) in the biotic domain of Eukaryota. By phyletic definition, these many-celled, sub- vertebrate animals lack a vertebral column, spinal column, vertebrae, backbone, or long, full-length notochord—in contrast to the vertebrates in the one phylum of Chordata. Relatedly, invertebrates have never had a cartilaginous or boney internal skeleton, with its skeletal supports, gill slits, ribs and jaws.
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Serpula (also known as calcareous tubeworm, serpulid tubeworm, fanworm, or plume worm) is a genus of sessile, marine annelid tube worms that belongs to the family Serpulidae. Serpulid worms are very similar to tube worms of the closely related sabellid family, except that the former possess a cartilaginous operculum that occludes the entrance to their protective tube after the animal has withdrawn into it. The most distinctive feature of worms of the genus Serpula is their colorful fan-shaped "crown". The crown, used by these animals for respiration and alimentation, is the structure that is most commonly seen by scuba divers and other casual observers.
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Wobbegong sharks are a species located under the elasmobranch subclass of Chondrichthyes, meaning the wobbegongs are cartilaginous fish with 4-7 gill slits. Elasmobranch fish have survived four mass-extinctions, and it is speculated that members of the elasmobranch lineage (including western wobbegong sharks) are related to ancestors from the Mesozoic period. The orectolobidae genus of sharks likely diversified from their other ancestors in the Miocene age, which may explain the high distribution of wobbegongs within the Inso-Australian region. It is suspected that there was a rapid spreading of wobbegong sharks within the last 2 million years, despite there being a lack of an extensive fossil record.
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With age, the cap surface becomes smooth, the color dark brownish-gray to black beneath the bloom, fading slowly to a pale gray, and nearly pinkish-buff at times. The cap margin is opaque and frequently has narrow, deep furrows or grooves, with the surface often more or less uneven and appearing as if streaked with glistening lines. The flesh is very hard and cartilaginous, watery grayish to white, rather thin, and with no distinctive odor and a mild taste. The gills are narrowly adnate (attached squarely to the stem) or have a short decurrent tooth, and are packed close together, with 30–38 gills reaching the stem.
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The name Collybia means "small coin". Later in his systematic work of 1838, Fries characterized Collybia as those species with #white spores, #incurved cap margin, #central cartilaginous stipe, and #fruit bodies which decay easily ("putrescent"). The last criterion divided these mushrooms from those of Marasmius, which had the property of being able to revive after having dried out (called "marcescent"). Although Fries considered this an important characteristic, some later authors like Charles Horton Peck (1897) and Calvin Henry Kauffman (1918) did not agree with Fries's criteria for the classification, and Gilliam (1976) discarded marcescence as a characteristic for the identification and differentiation of these genera.
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The superior oblique muscle originates at the back of the orbit (a little closer to the medial rectus, though medial to it), getting rounder as it courses forward to a rigid, cartilaginous pulley, called the trochlea, on the upper, nasal wall of the orbit. The muscle becomes tendinous about 10mm before it passes through the pulley, turning sharply across the orbit, and inserts on the lateral, posterior part of the globe. Thus, the superior oblique travels posteriorly for the last part of its path, going over the top of the eye. Due to its unique path, the superior oblique, when activated, pulls the eye downward and laterally.
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The great white shark (Carcharodon carcharias), also known as the great white, white shark or "white pointer", is a species of large mackerel shark which can be found in the coastal surface waters of all the major oceans. It is notable for its size, with larger female individuals growing to in length and in weight at maturity. However, most are smaller; males measure , and females measure on average. According to a 2014 study, the lifespan of great white sharks is estimated to be as long as 70 years or more, well above previous estimates, making it one of the longest lived cartilaginous fishes currently known.
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Degeneration of intervertebral disc (IVD) is the main cause of neck and low back pain. The IVD is composed of a gelatinous nucleus pulposus (NP) centre and several surrounding coaxial lamellae that form the inner and outer anulus fibrosus. This unique structural feature allows the IVD to constrain motion at high loads and provide flexibility at low loads. While factors such as abnormal mechanical stresses, biochemical imbalances and nutritional and genetic deficiencies are all reported to play a role in disc degeneration, the natural aging process is also characterised by replacement of the gelatinous nucleus pulposus region of the disc by a less-flexible cartilaginous disc.
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Chondrus crispus—commonly called Irish moss or carrageen moss (Irish carraigín, "little rock")—is a species of red algae which grows abundantly along the rocky parts of the Atlantic coast of Europe and North America. In its fresh condition this protist is soft and cartilaginous, varying in color from a greenish-yellow, through red, to a dark purple or purplish-brown. The principal constituent is a mucilaginous body, made of the polysaccharide carrageenan, which constitutes 55% of its dry weight. The organism also consists of nearly 10% dry weight protein and about 15% dry weight mineral matter, and is rich in iodine and sulfur.
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Gruber and Sparks (2015) have observed the first fluorescence in a marine tetrapod (four- limbed vertebrates). Sea turtles are the first biofluorescent reptile found in the wild. According to Gruber and Sparks (2015), fluorescence is observed in an increasing number of marine creatures (cnidarians, ctenophores, annelids, arthropods, and chordates) and is now also considered to be widespread in cartilaginous and ray-finned fishes. The two marine biologists accidentally made the observation in the Solomon Islands on a hawksbill sea turtle, one of the rarest and most endangered sea turtle species in the ocean, during a night dive aimed to film the biofluorescence emitted by small sharks and coral reefs.
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The other recently-surviving member of this lineage is the possibly now extinct Chinese paddlefish (Psephurus gladius) endemic to the Yangtze River basin in China. The American paddlefish is often referred to as a primitive fish or a relict species because it retains some morphological characteristics of its early ancestors, including a skeleton that is almost entirely cartilaginous and a paddle-shaped rostrum (snout) that extends nearly one-third their body length. It has been referred to as a freshwater shark because of its heterocercal tail or caudal fin resembling that of sharks. The American paddlefish is a highly derived fish because it has evolved with adaptations such as filter feeding.
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A nasal septum perforation is a medical condition in which the nasal septum, the bony/cartilaginous wall dividing the nasal cavities, develops a hole or fissure. This may be brought on directly, as in the case of nasal piercings, or indirectly, as by long-term topical drug application, including intranasal ethylphenidate, methamphetamine, cocaine, crushed prescription pills, or decongestant nasal sprays, chronic epistaxis, excessive nose picking and as a complication of nasal surgery like septoplasty or rhinoplasty. Much less common causes for perforated nasal septums include rare granulomatous inflammatory conditions like granulomatosis with polyangiitis. It has been reported as a side effect of anti-angiogenesis drugs like bevacizumab.
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A portrait of Klein, from his time as Secretary of Danzig, featured in Historiae Piscium Naturalis Klein published Historiae Piscium Naturalis promovendae Missus primus Gedani in 1744. The publication, dedicated to the Royal Society, focused on understanding the auditory capacity of cartilaginous and spinose fishes. According to John Eames, until the publication of the work, it was believed to have been understood that only cetaceous fish were known to have auditory passages, or ear holes, and that the question of whether fish could hear was still not understood. Aristotle claimed, in his "History of Animals," that fishes possessed no evident auditory organs, but believed that nonetheless they must hear.
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Liocranchia reinhardti In the cranchiids Leachia cyclura and Liocranchia reinhardti, the dermal tubercles are not distributed throughout the mantle but arranged in discrete cartilaginous bands. A role in buoyancy control is therefore unlikely. One possibility is that these rigid bands play a pseudoskeletal role, maintaining the shape of parts of the mantle during swimming contractions or providing attachment points for mantle muscles or visceral tissue (such as the septum covering the coelom). The very dense tuberculate ridges found on the arms and dorsal mantle of Histioteuthis meleagroteuthis may similarly provide insertion points for muscles, and are probably most important in juvenile animals, which lack well-developed musculature.
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They are first represented in the fossil record from the Silurian by two groups of fish: the armoured fish known as placoderms, which evolved from the ostracoderms; and the Acanthodii (or spiny sharks). The jawed fish that are still extant in modern days also appeared during the late Silurian: the Chondrichthyes (or cartilaginous fish) and the Osteichthyes (or bony fish). The bony fish evolved into two separate groups: the Actinopterygii (or ray- finned fish) and Sarcopterygii (which includes the lobe-finned fish). During the Devonian period a great increase in fish variety occurred, especially among the ostracoderms and placoderms, and also among the lobe-finned fish and early sharks.
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As an adaptation for navigating its complex reef environment, the epaulette shark moves by seemingly walking, bending its body from side-to-side and pushing off of the substrate with its paddle-shaped pectoral and pelvic fins. Its gait is similar to that of salamanders, an example of convergent evolution. The shark is capable of swimming, but often prefers to walk along the sandy or coral bottom even when the water is deep enough to allow it to swim freely. The cartilaginous supports of the epaulette shark's paired fins are reduced and separated when compared to other sharks, allowing them to be rotated for use as limbs.
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Graneledone yamana is a species of octopus in the genus Graneledone. G. yamana is assigned to this genus because of the absence of an ink sac and crop, the presence of cartilaginous warts covering the body cavity, uniserial suckers on the arms, and a reduced radula. This genus has been found in the deep waters of the Atlantic Ocean near hydrothermal vents. Its identifying characteristics are papillose skin, two horns located above the eyes, small gills, and five to seven lamellae located on the outside of the demibranch. The arms of G. yamana have 35–80 suckers on the females and 26–70 on the males.
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Then it grew longer and stronger, and acquired muscles capable of closing the developing jaw. In early fish and in chondrichthyans (cartilaginous fish such as sharks), Meckel's cartilage continued to be the main component of the lower jaw. But in the adult forms of osteichthyans (bony fish) and their descendants (amphibians, reptiles, birds and mammals) the cartilage was covered in bone – although in their embryos the jaw initially develops as the Meckel's cartilage. In tetrapods the cartilage partially ossifies (changes to bone) at the rear end of the jaw and becomes the articular bone, which forms part of the jaw joint in all tetrapods except mammals.
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In it, the authors suggested that the skull would have supported a short trunk, or "hog's snout" as well as fleshy upper and lower lips. The anteriorly directed nares and the absence of a bony nasal septum (which presumably indicates cartilaginous tissue serving its place) provide evidence for a trunk-like snout, while striations on the surface of the nasal bones and the lower jaw most likely acted as attachment points for the nasolabial muscles and the depressor muscle, respectively.Fiorelli, L. E. (2005). "Nuevos restos de Notosuchus terrestris Woodward, 1896 (Crocodyliformes: Mesoeucrocodylia) del Cretácico Superior (Santoniano) de la Provincia de Neuquén, Patagonia, Argentina". 79p.
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268–274 The majority of teleost species belong to the clade Euteleostei, which consists of 17,419 species classified in 2,935 genera and 346 families. Shared traits of the euteleosts include similarities in the embryonic development of the bony or cartilaginous structures located between the head and dorsal fin (supraneural bones), an outgrowth on the stegural bone (a bone located near the neural arches of the tail) and caudal median cartilages located between hypurals of the caudal base. The majority of euteleosts are in the clade Neoteleostei. A derived trait of neoteleosts is a muscle that controls the pharyngeal jaws, giving them a role in grinding food.
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Around the sixth week of gestation, six swellings of tissue called the hillocks of Hiss arise around the area that will form the ear canal. These eventually coalesce to form the outer ear. Darwin's tubercle is a minor malformation of the junction of the fourth and fifth hillocks of Hiss. It is found in a substantial minority of people and takes the form of a cartilaginous node or bump on the rim of their outer ear, which is thought to be the vestige of a joint that allowed the top part of the ancestral ear to swivel or flop down over the opening to the ear.
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The dorsal vertebrae are more rounded with flat spines; the first three or four carry ribs that contact the sternal ribs; the more posterior ribs contact the gastralia. The first five or six, rather short, caudal vertebrae form a flexible tail base. To the back the caudals grow longer and are immobilised by their intertwining extensions with a length of up to five vertebrae which together surround the caudals with a bony network, allowing the tail to function as a rudder. D. banthensis restoration; the tail form is hypothetical The breastbone is triangular and relatively small; Padian has suggested it may have been extended at its back with a cartilaginous tissue.
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The researchers found that the dinosaur could have had either a scroll-shaped turbinate (like in a turkey) or a branched one (as in an ostrich) as both could have directed air to the olfactory region. The blood vessel system in the passages also suggest that the turbinates served to cool down warm arterial blood from the body that was heading to the brain. The skull of S. validum specimen UALVP 2 was suited for a study of this kind due to its exceptional preservation; it has ossified soft tissue in the nasal cavity, which would otherwise be cartilaginous and therefore not preserved through mineralization.
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The superior ovary in the center of the flower consists of three merged carpels, that together protect three cavities within which are one to four anatropous ovules each of which is covered by a single layer. The upright style tapers towards the top and carries a small globe-shaped stigma or expands towards the top into an inverted cone-shaped stigma, covered in small grains. The smooth, cartilaginous, dehiscent fruit opens with three valves. The small, dark reddish brown seeds are ellipsoid in shape either with a smoothed netted structure or angular with three sutures and with prominent warts or a honeycomb-like structure.
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Six gill slits in a bigeyed sixgill shark; most sharks have only five Sharks and rays typically have five pairs of gill slits that open directly to the outside of the body, though some more primitive sharks have six or seven pairs. Adjacent slits are separated by a cartilaginous gill arch from which projects a long sheet-like septum, partly supported by a further piece of cartilage called the gill ray. The individual lamellae of the gills lie on either side of the septum. The base of the arch may also support gill rakers, small projecting elements that help to filter food from the water.
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Stingrays are a type of demersal, cartilaginous fish common to the South Carolina coast as well as other areas on the Atlantic shoreline. Typically, stingrays avoid contact with humans unless they are accidentally stepped upon, a situation often ending in a stingray injury, where the stingray punctures the human with its poisonous barb. While these injuries are extremely painful, they are not usually life-threatening as long as they are properly attended to by a medical professional. The saltmarsh estuaries of Hilton Head Island are the feeding grounds, breeding grounds, and nurseries for many saltwater species of game fish, sport fish, and marine mammals.
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Cartilage in the second pharyngeal arch is referred to as Reichert's cartilage and contributes to many structures in the fully developed adult.Sudhir, Sant, 2008.Embryology for Medical Students 2nd edition In contrast to the Meckel's cartilage of the first pharyngeal arch it does not constitute a continuous element, and instead is composed of two distinct cartilaginous segments joined by a faint layer of mesenchyme. Dorsal ends of Reichert's cartilage ossify during development to form the stapes of the middle ear before being incorporated into the middle ear cavity, while the ventral portion ossifies to form the lesser cornu and upper part of the body of the hyoid bone.
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To obtain what Cheyne called a "Green Old Age", he advised a wise man who wanted to live on to seventy or eighty to begin at least at the age of fifty to lessen his daily intake of meat and drink, especially in quantity. This was because about this time the "great Crise or Climacteric of Life" generally began in both sexes. For it was then, Cheyne argued, that the blood and the juices of the most healthy and strong began to cool, to thicken and were becoming "vapid" and obstructed in the "Capillaries and Lymphatics". As a result many of these vessels coalesced and became cartilaginous”.
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Because cartilaginous fishes are the oldest living group of jawed vertebrates, the Australian ghostshark genome will serve as a useful reference genome for understanding the origin and evolution of vertebrate genomes including humans, which shared a common ancestor with the Australian ghostshark about 450 million years ago. Studies so far have shown the sequence and the gene order (synteny) are more similar between human and elephant shark genomes than between human and teleost fish genomes (pufferfish and zebrafish), though humans are more closely related to teleost fishes than to the Australian ghostshark. The Elephant Shark Genome Project was launched with the aim to sequence the whole genome of the elephant shark.
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Holosteans share with other non- teleost ray-finned fish a mixture of characteristics of teleosts and sharks. In comparison with the other group of non-teleost ray-finned fish, the chondrosteans, the holosteans are closer to the teleosts and further from sharks: the pair of spiracles found in sharks and chondrosteans is reduced in holosteans to a remnant structure: in gars, the spiracles do not even open to the outside;Ontario. Game and fish commission the skeleton is lightly ossified: a thin layer of bone covers a mostly cartilaginous skeleton in the bowfins. In gars, the tail is still heterocercal but less so than in the chondrosteans.
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In jawless fishes a series of gills opened behind the mouth, and these gills became supported by cartilaginous elements. The first set of these elements surrounded the mouth to form the jaw. There are ample evidences For example: (1) both sets of bones are made from neural crest cells (rather than mesodermal tissue like most other bones); (2) both structures form the upper and lower bars that bend forward and are hinged in the middle; and (3) the musculature of the jaw seem homologous to the gill arches of jawless fishes. (Gilbert 2000) that vertebrate jaws are homologous to the gill arches of jawless fishes.
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Predominantly piscivorous, this species is known to prey upon hagfish and at least 50 species of bony fishes, including fast-swimming types that inhabit open water; significant prey species include the mackerel Scomber japonicus, the sardine Sardinops melanostictus, the filefish Thamnaconus modestus, and the hakeling Physiculus japonicus. Unusually for such a small shark, it also feeds on at least 10 species of cartilaginous fishes, including lantern sharks, catsharks (particularly the cloudy catshark, Scyliorhinus torazame, and its eggs), the electric ray Narke japonica, and skates (including their eggs). It also cannibalizes smaller members of its own species. Cephalopods, mostly the squid Doryteuthis bleekeri and the cuttlefish Sepia spp.
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The quadrate and the maxillary and palatopterygoid arches are more or less movable to allow for the distension required by the passage of prey, often much exceeding the size of the mouth. For the same reason, the rami of the lower jaw, which consist of dentary, splenial, angular, and articular elements, with the addition of a coronoid in the boas and a few other small families, are connected at the symphysis by a very extensible elastic ligament. The hyoid apparatus is reduced to a pair of cartilaginous filaments situated below the trachea, and united in front. There are various modifications according to the genera.
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The investigation of the birth was conducted by the research team from Queen's University Belfast, Southeastern University in Florida, and Henry Doorly Zoo itself, and it was concluded after DNA testing that the reproduction was parthenogenetic. The testing showed the female pup's DNA matched only one female who lived in the tank, and that no male DNA was present in the pup. The pup was not a twin or clone of her mother, but rather, contained only half of her mother's DNA ("automictic parthenogenesis"). This type of reproduction had been seen before in bony fish, but never in cartilaginous fish such as sharks, until this documentation.
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Raja stellulata, commonly known as the Pacific starry skate, rock skate, prickly skate, or starry skate, is a species of cartilaginous fish in the family Rajidae. It is found on rocky bottoms at 18–982 m depths (typically 70–150 m) in the Northeast and Eastern Central Pacific, from Coronado Bank in northern Baja California in Mexico to Barkley Sound in British Columbia, Canada. Females reach a maximum total length of 76.1 cm and a maximum age of 15 years, while males can be up to 71.7 cm long and live up to 14 years; the total length at birth is 15.5–22.5 cm. This skate prefers cold water with a temperature of 4.1–11.6°C (average 8.9°C).
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Myctophum punctatum Lanternfish typically have a slender, compressed body covered in small, silvery deciduous cycloid scales (ctenoid in four species), a large bluntly rounded head, large elliptical to round lateral eyes (dorsolateral in Protomyctophum species), and a large terminal mouth with jaws closely set with rows of small teeth. The fins are generally small, with a single high dorsal fin, a forked caudal fin, and an adipose fin. The anal fin is supported by a cartilaginous plate at its base, and originates under, or slightly behind, the rear part of the dorsal fin. The pectoral fins, usually with eight rays, may be large and well-developed to small and degenerate, or completely absent in a few species.
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The cap surface is smooth and moist, with a slimy margin that is initially pressed against the stipe; with age the margin becomes notched and sometimes scalloped, turning translucent. The cap color is dark gray to pale gray, somewhat hygrophanous, fading to ashy white or brown when dry. The flesh is thin, gray, cartilaginous and tough, with a strongly farinaceous (mealy, similar to raw potatoes) odor and taste if crushed or chewed. The whitish to grayish gills are moderately broad (2–3 mm) with a spacing that is close to subdistant, and 18–26 reach the stipe, interspersed with two or three tiers of lamellae (short gills that do not extend fully from the cap margin to the stipe).
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Although cartilaginous skeletons do not fossilize, O. megalodon is estimated to have been considerably larger than the great white shark, estimated at up to . Similarities among the physical remains and the extreme size of both the great white and O. megalodon led many scientists to believe these sharks were closely related, and the name Carcharodon megalodon was applied to the latter. However, a new hypothesis proposes that the great white is also more closely related to an ancient mako shark, Isurus hastalis, than to the O. megalodon. The theory seems to be supported with the earlier discovery of a complete set of jaws with 222 teeth and 45 vertebrae of the extinct transitional species Carcharodon hubbelli in 1988.
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In the majority of vertebrates, the mesonephros persists into the adult, albeit usually fused with the more advanced metanephros; only in amniotes is the mesonephros restricted to the embryo. The kidneys of fish and amphibians are typically narrow, elongated organs, occupying a significant portion of the trunk. The collecting ducts from each cluster of nephrons usually drain into an archinephric duct, which is homologous with the vas deferens of amniotes. However, the situation is not always so simple; in cartilaginous fish and some amphibians, there is also a shorter duct, similar to the amniote ureter, which drains the posterior (metanephric) parts of the kidney, and joins with the archinephric duct at the bladder or cloaca.
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Reconstructed skull of the holotype in lateral (A) and dorsal (C) views The snout is moderately elongated, with a premaxilla featuring elongated nasal processes. A fine, vertical lamina of bone is connected rostrally to the medial margin of the premaxilla, indicating that when the animal was alive, a cartilaginous internasal septum was present. Additional to this, the premaxilla features lateral and medial foramina that are connected by a complex system of vascular canals, which pervades the structure of the premaxilla and is probably associated with the sensory branches of the neurovasculature and ophthalmic nerve supporting the rhamphotheca (beak). The maxilla is triangular in shape and preserves 24 alveoli, the teeth are homodont with coarse serrations.
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L. tomentosum is the only species assigned to the section Leucospermum that has (some) upright branches and an underground rootstock. It can be distinguished from the other Leucospermum species by the combination of small, cartilaginous, tightly overlapping bracts subtending the flower heads with short, soft hair on the outer surface, and leaves line-shaped, gully- shaped in cross section. It can be confused with L. rodolentum that develops a single trunk at its base, L. parile that also develops a single trunk at its base and in addition has pointed involucral bracts and L. hypophyllocarpodendron subsp. canaliculatum, which shares that it has many stems from the ground, but differs in having rounded involucral bracts.
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The radulae and cartilaginous oral bolsters of the Gadilidae are structured like zippers where the teeth actively crush the prey by opening and closing on it repeatedly, while the radulae and bolsters of the Dentaliidae work rachet-like to pull the prey into the esophagus, sometimes whole. The massive radula of the scaphopods is the largest such organ relative to body size of any mollusc (among whom, except for the bivalves, the presence of a which is a defining characteristic). The remainder of the digestive system consists of a digestive diverticulum, esophagus, stomach, and intestine. A digestive gland secretes enzymes into the stomach, but, unlike some other molluscs, does not digest the food directly itself.
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The Norman Castle in Ariano Irpino. Tourist destinations are the Sanctuaries of Montevergine, San Gerardo Maiella of Caposele and San Francesco a Folloni; the ski resort of Laceno; the Norman Castle and the Cathedral Church of Ariano Irpino, the archeological areas of Avella and Aeclanum, the Lancellotti castle in Lauro, the medieval town of Gesualdo, the Roman ruins of Abellinum and the early Christian basilica in Prata. The Selachoidei National Gallery at Avellino houses one of the largest collections of cartilaginous fishes in the country. Natural attractions include the Monti Piacentini and Partenio Regional Parks, together with two WWF sites, Valle della Caccia in Senerchia and the area around the Ofanto dam in Conza della Campania.
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Although during preparation, a cast had been made of the fossil beforehand to document the original relative positions of the bones. Carpal bones were not known from any specimen, leading some authors to suggest that they were lost in the genus. In a 2016 paper, Matthew Carrano and Jonah Choiniere suggested that one or more cartilaginous (not bony) carpals were probably present, as indicated by a gap present between the forearm bones and the metacarpals, as well as by the surface texture within this gap seen in the cast. In contrast to most more-derived theropods, which showed only three digits on each manus (digits I–III), Ceratosaurus retained four digits, with digit IV reduced in size.
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In fish, barbels can take the form of small, fleshy protrusions or long, cylindrical shaped extensions of the head of a fish. The cylindrical barbel shapes are built on an internal support system that can be made from ossified tissue or from cartilaginous connective tissue that provides a base for blood vessels and myelinated nerves to wrap around, held together in the dermis. Muscle tissue in the central region of the barbel allows the structure limited movement that aids in prey manipulation. On the epidermis, taste buds are situated on dermal papillae, small ridges of folded skin that increase the surface area of the skin and the total number of taste buds that can be concentrated on the barbel.
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Oscarella lobularis has been used as a model organism for the study of evolutionary biology and developmental biology, being particularly suitable because of its easy availability, its simple histology and cell composition, its robust epithelial structures and because it lacks a skeleton. Researchers have studied the different colour morphs of this sponge which sometimes grow alongside each other. There appears to be a cryptic complex and two species that had been synonymised in 1877 have been redescribed as O. lobularis (violet in colour) and O. tuberculata; these species can be distinguished from each other cytologically, and by the former having a soft consistency and the latter a cartilaginous consistency. Several other new species have been described, mostly from caves.
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For example: (1) both sets of bones are made from neural crest cells (rather than mesodermal tissue like most other bones); (2) both structures form the upper and lower bars that bend forward and are hinged in the middle; and (3) the musculature of the jaw seem homologous to the gill arches of jawless fishes. (Gilbert 2000) In jawless fishes a series of gills opened behind the mouth, and these gills became supported by cartilaginous elements. The first set of these elements surrounded the mouth to form the jaw. The upper portion of the second embryonic arch supporting the gill became the hyomandibular bone of jawed fishes, which supports the skull and therefore links the jaw to the cranium.
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Finned sharks Shark fin protest at Maxim's restaurant at the University of Hong Kong 10 February 2018 Shark fins used in the soup are the cartilaginous dorsal, pectoral and caudal fins. These are regularly harvested by a process known as shark finning, which takes only the fins and discards the carcass, alive or dead. Overfishing poses a major threat to the world's shark populations. Some groups, such as Fins Attached, Shark Savers, IUCN, Shark Angels, Shark Whisperer and the Sea Shepherd Conservation Society, discourage consumption of the soup due to concerns with the world's shark population and how sharks are inhumanely finned alive and returned to the ocean, unable to swim, hunt or survive.
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Then it draws the sides of its throat together, forcing the water through the gill openings, so that it passes over the gills to the outside. The bony fish have three pairs of arches, cartilaginous fish have five to seven pairs, while the primitive jawless fish have seven. The vertebrate ancestor no doubt had more arches, as some of their chordate relatives have more than 50 pairs of gills. Higher vertebrates do not develop gills, the gill arches form during fetal development, and lay the basis of essential structures such as jaws, the thyroid gland, the larynx, the columella (corresponding to the stapes in mammals) and in mammals the malleus and incus.
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The tensor veli palatini tenses the soft palate and by doing so, assists the levator veli palatini in elevating the palate to occlude and prevent entry of food into the nasopharynx during swallowing. The tensed palate consequently provides a stable platform for elevation of the pharynx during swallowing by the pharyngeal muscles. Since it is also attached to the lateral cartilaginous lamina of the auditory tube (also known as the Eustachian tube), it assists in its opening during swallowing or yawning to allow air pressure to equalize between the tympanic cavity and the outside air. Equalization of air pressure in the tympanic cavity is essential for preventing damage to the tympanic membrane and a resulting loss of hearing acuity.
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The octopus (along with cuttlefish) has the highest brain-to-body mass ratios of all invertebrates; it is also greater than that of many vertebrates. It has a highly complex nervous system, only part of which is localised in its brain, which is contained in a cartilaginous capsule. Two-thirds of an octopus's neurons are found in the nerve cords of its arms, which show a variety of complex reflex actions that persist even when they have no input from the brain. Unlike vertebrates, the complex motor skills of octopuses are not organised in their brain via an internal somatotopic map of its body, instead using a nonsomatotopic system unique to large-brained invertebrates.
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Two of Jude and Rhoda's grandsons, Moses and Aaron, served in the Civil War. Jude and Rhoda's nephew was the Exeter-born abolitionist poet James Monroe Whitfield. In his history of the town of Exeter, published in 1888, Charles Henry Bell penned a memorable description of Jude Hall as "a man of powerful physique...it is said that the parts of his ribs which are usually cartilaginous were of solid bone, so that his vital organs were enclosed in a sort of osseous case."Boston: J.E. Farwell & Co., 1888 According to Bell, Hall was the chief witness of the government in the trial of John Blaisdell for the 1822 homicide of another Exeter resident, John Wadleigh.
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It has five constant domains (CH) per chain instead of the usual three, several disulfide bonds in unusual positions, and the complementarity-determining region 3 (CDR3) forms an extended loop covering the site which binds to a light chain in other antibodies. These differences, in combination with the phylogenetic age of the cartilaginous fishes, have led to the hypothesis that IgNAR could be more closely related to a primordial antigen-binding protein than the mammalian immunoglobulins. To test this hypothesis, it would be necessary to discover IgNAR or similar antibodies in vertebrates that are phylogenetically still older, like the jawless fish lamprey and hagfish. Non-vertebrates do not have antibodies at all.
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The winging of the stipe extends up the rachis; it is variously described as taking the form of parallel, cartilaginous ribs, with a narrow, green, leafy wing, the ribs fusing into a wing towards the tip of the leaf, or a whitish to tan wing similar in dimensions to that of the stipe. The blade is cut into pinnae throughout its length, from 20 to 40 pairs per leaf. The pinnae are sessile (stalkless) or have minute stalks and are rectangular in shape, tapering slightly toward the tip. In North American and Mexican material, those in the middle of the leaf blade measure from in length (rarely as small as ) and from in width.
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The biosphere reserve is situated in a transition zone between Australian and Asian flora and fauna habitats. Terrestrial ecosystems include open grass land,- woodland savannah, tropical deciduous (monsoon) forest, mangroves and quasi cloud forest. The marine area constitutes 70.2% of the biosphere reserve and is characterized by a combination of strong currents, coral reefs and islets, which make navigation around the islands in Komodo National Park difficult and dangerous. Komodo has one of the world's richest marine environments, including over 260 species of reef building coral, 70 species of sponge, ascidians, marine worms, mollusks, echinoderms, crustaceans, cartilaginous, over 1,000 species of bony fishes, marine reptiles (green turtle and hawksbill turtle), and marine mammals (dolphins, whales, and dugongs).
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Down the middle of the sublingua is a thick strengthening rod called the plica mediana or lytta, which connects the sublingua to the underside of the tongue, and is part of the lingual septum (septum of the tongue). The thickness and size of the plica mediana can vary between species, and except in treeshrews, it is cartilaginous and provides support for the sublingua. Only the serrated and often keratinized tip of the sublingua is free to move small distances along the underside of the tongue, while the majority of its length adheres to the underside of the tongue. These free-moving folds or filaments are called the plica fimbriata and attach to the base of the sublingua and are supported at the midline by the plica mediana.
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Newer research suggests that a branch of Placoderms was most likely the ancestor of present- day gnathostomes. A 419-million-year-old fossil of a placoderm named Entelognathus had a bony skeleton and anatomical details associated with cartilaginous and bony fish, demonstrating that the absence of a bony skeleton in Chondrichthyes is a derived trait.Scientists make jaw dropping discovery The fossil findings of primitive bony fishes such as Guiyu oneiros and Psarolepis, which lived contemporaneously with Entelognathus and had pelvic girdles more in common with placoderms than with other bony fish, show that it was a relative rather than a direct ancestor of the extant gnathostomes. It also indicates that spiny sharks and Chondrichthyes represent a single sister group to the bony fishes.
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Since the blood of ray-finned fishes contains more salt than freshwater, they could simply get rid of ammonia through their gills. When they finally returned to the sea again, they did not recover their old trick of turning ammonia to urea, and they had to evolve salt excreting glands instead. Lungfishes do the same when they are living in water, making ammonia and no urea, but when the water dries up and they are forced to burrow down in the mud, they switch to urea production. Like cartilaginous fishes, the coelacanth can store urea in its blood, as can the only known amphibians that can live for long periods of time in salt water (the toad Bufo marinus and the frog Rana cancrivora).
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Their species include 56 of cartilaginous fishes and 386 of bony fishes. The 266 species of inland fishes belong to 61 families, of which Cyprinidae is the largest, having 61 species. There are also 55 species of catfishes found in the fresh waters of Bangladesh. The amphibians in Bangladesh include only the species of the order Anura. From the 22 amphibian species, 8 are recognized as threatened. The number of reptiles species found is 126 which includes 109 inland and 17 marine species. From the 109 inland reptiles, 2 are crocodilians, 21 turtles and tortoises, 18 lizards, and 67 snakes. The marine reptiles comprise 12 snakes and 5 turtles. There are 628 species of birds found in Bangladesh under 16 orders and 67 families, including 276 passerines.
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A smalltooth sand tiger at a hydrothermal vent on the Kasuga-2 submarine volcano: Smaller individuals such as this tend to remain in deeper water. Compared to the grey nurse shark, the dentition of the smalltooth sand tiger is less robust and lacks specialized cutting and crushing teeth, suggesting that it tends to tackle smaller prey. The diet of the smalltooth sand tiger consists of bottom-dwelling bony fishes such as rockfish (Sebastes spp.), invertebrates such as squid, shrimp, and possibly marine isopods, and cartilaginous fishes including rays and chimaeras. The largest known prey item taken by this species was a 1.3-m-long (4.3 ft) kitefin shark (Dalatias licha), found inside the stomach of a 2.9-m-long (9.5 ft) male from New Caledonia.
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P. monroensis lived alongside Mixopterus, Hughmilleria, Eurypterus and Carcinosoma. P. nobilis lived alongside representatives of Acutiramus, Erettopterus and Eusarcana as well as with a diverse fauna of conodonts, gastropods, cephalopods, ostracods, malacostracans, trilobites and bivalves and cartilaginous fish Onchus. In the Early Devonian Dundee Formation of Scotland, fossils of P. anglicus occur together with a wide array of different eurypterids, including Erieopterus, Pagea, Tarsopterella and Stylonurus, as well as acanthodian fish Ischnacanthus and Mesacanthus, shark Climatius and osteostracian fish Cephalaspis. Fossils of P. carmani of similar age found in the Holland Quarry Shale Formation of Ohio also preserve a diverse Devonian fauna of various eurypterids, such as Dolichopterus, Strobilopterus and Erettopterus, as well as pteraspidomorph fish Allocrytaspis and placoderm fish Aethapsis.
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Each flower head contains as many as 25–35 individual flowers, while those lower down usually contain the fewest flowers. The bracts that encircle the flower heads are tightly overlapping. The bracts in the outer whorl are oval with a blunt tip, later slightly spade-shaped, 5–10 mm (0.2–0.4 in) long and 2–3 mm (0.08–0.12 in) wide, covered in dense woolly hairs at the base, rounded, thickened, and eventually hairless at the tip. The bracts in the inner whorl are 6–8 mm (¼–⅓ in) long and 1–1½ mm (0.04–0.06 in) wide, lance-shaped with a pointy tip, covered in dense silky hairs, cartilaginous in consistency but growing three to four times as large an becoming woody after fertilisation.
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There are substantial fossil records of jawed fishes across the K–Pg boundary, which provide good evidence of extinction patterns of these classes of marine vertebrates. While the deep sea realm was able to remain seemingly unaffected, there was an equal loss between the open marine apex predators and the durophagous demersal feeders on the continental shelf. Within cartilaginous fish, approximately 7 out of the 41 families of neoselachians (modern sharks, skates, and rays) disappeared after this event and batoids (skates and rays) lost nearly all the identifiable species, while more than 90% of teleost fish (bony fish) families survived. In the Maastrichtian age, 28 shark families and 13 batoid families thrived, of which 25 and 9, respectively, survived the K–T boundary event.
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DPB is distinguished by the presence of lesions that appear on X-rays as nodules in the bronchioles of both lungs; inflammation in all tissue layers of the respiratory bronchioles; and its higher prevalence among individuals with East Asian lineage. DPB and bronchiolitis obliterans are two forms of primary bronchiolitis. Specific overlapping features of both diseases include strong cough with large amounts of often pus-filled sputum; nodules viewable on lung X-rays in the lower bronchi and bronchiolar area; and chronic sinusitis. In DPB, the nodules are more restricted to the respiratory bronchioles, while in OB they are often found in the membranous bronchioles (the initial non-cartilaginous section of the bronchiole, that divides from the tertiary bronchus) up to the secondary bronchus.
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Although it is usually assumed that a single passage served for this purpose, Prieto- Márquez and Wagner saw indications in the form of the nasal that there were paired downward passages, to the inside of the lateral processes of the praemaxillae. From this they concluded that the entire airflow was likely separated, the common medium chamber probably being divided into a left and right section by a cartilaginous septum. The conclusion that the tubular structure in the rear nasal bones was not an air passage, forced Prieto- Márquez and Wagner to find an alternative explanation of its function. They suggested that it would have served to lessen the weight of the crest, such a tube combining relative strength with a low bone mass.
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Size of Ptychodus vs an average sized human Ptychodus was about long and was unearthed in Kansas, United States."BBC - Earth News - Giant predatory shark fossil unearthed in Kansas" It was covered in placoid scales like other members of Hybodontoidea, reinforced with a large cartilaginous skeleton, and was a bearer of large serrated spines along the dorsal fin.A Field Guide to Fossils of the Smoky Hill Chalk Unlike the colossal nektonic planktivores Rhincodon (whale sharks) and Cetorhinus (basking sharks) which relied upon gill rakers to acquire their food, the Ptychodus had a massive arrangement crushing plate teeth. A Ptychodus jaw contains many teeth, up to 550 teeth, 220 of which are on the lower jaw and 260 in the upper jaw.
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The rib cage is the arrangement of ribs attached to the vertebral column and sternum in the thorax of most vertebrates, that encloses and protects the heart and lungs. In humans, the rib cage, also known as the thoracic cage, is a bony and cartilaginous structure which surrounds the thoracic cavity and supports the shoulder girdle to form the core part of the human skeleton. A typical human rib cage consists of 24 ribs in 12 pairs, the sternum and xiphoid process, the costal cartilages, and the 12 thoracic vertebrae. Together with the skin and associated fascia and muscles, the rib cage makes up the thoracic wall and provides attachments for the muscles of the neck, thorax, upper abdomen, and back.
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Due to the slightly-raised cartilaginous ear base, the head of many lop rabbits (with the exception of English Lops) has a small bulge, referred to as the crown. The head of a typical lop rabbit is said to resemble that of a male sheep in profile, thus the German term for a lop rabbit (Widder, meaning Aries [the ram]), the French term (bélier, meaning ram) and the Italian term (ariete, from Latin aries). A rabbit's ear, with its blood vessels close to the surface, is an essential thermoregulator, since rabbits cannot sweat. Longer ears are associated with warmer climates, and possibly even with a late-spring birth in cooler climates (when such rabbits are thought to develop summer ears).
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Their lower jaws usually have three rows of keradonts surrounded by a horny beak, but the number of rows can vary and the exact arrangements of mouth parts provide a means for species identification. In the Pipidae, with the exception of Hymenochirus, the tadpoles have paired anterior barbels, which make them resemble small catfish. Their tails are stiffened by a notochord, but does not contain any bony or cartilaginous elements except for a few vertebrae at the base which forms the urostyle during metamorphosis. This has been suggested as an adaptation to their lifestyles; because the transformation into frogs happens very fast, the tail is made of soft tissue only, as bone and cartilage take a much longer time to be broken down and absorbed.
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Restoration of a swimming Spinosaurus in its environment with contemporaneous aquatic animals The environment inhabited by Spinosaurus is only partially understood, and covers a great deal of what is now northern Africa. The region of Africa Spinosaurus is preserved in dates from 112 to 93.5 million years ago, although a potential specimen has been found in Campanian deposits. A 1996 study concluded from Moroccan fossils that Spinosaurus, Carcharodontosaurus, and Deltadromeus "ranged across north Africa during the late Cretaceous (Cenomanian)." Those Spinosaurus that lived in the Bahariya Formation of what is now Egypt may have contended with shoreline conditions on tidal flats and channels, living in mangrove forests alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Paralititan and Aegyptosaurus, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs.
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At birth, the three primary centers are quite separate, the crest, the bottom of the acetabulum, the ischial tuberosity, and the inferior rami of the ischium and pubis being still cartilaginous. By the seventh or eighth year, the inferior rami of the pubis and ischium are almost completely united by bone. About the thirteenth or fourteenth year, the three primary centers have extended their growth into the bottom of the acetabulum, and are there separated from each other by a Y-shaped portion of cartilage, which now presents traces of ossification, often by two or more centers. One of these, the os acetabuli, appears about the age of twelve, between the ilium and pubis, and fuses with them about the age of eighteen; it forms the pubic part of the acetabulum.
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This is a typical Cladodont tooth, of a shark called Glikmanius Cladodont (from Latin cladus, meaning branch and Greek Odon, meaning tooth) is the term for a common category of early Devonian shark known primarily for its "multi- cusped" tooth consisting of one long blade surrounded by many short, fork-like tines, designed to catch food that was swallowed whole, instead of being used to saw off chunks of meat like many modern sharks.Tooth retention in cladodont sharks: with a comparison between primitive grasping and swallowing, and modern cutting and gouging feeding mechanisms The skinny teeth would puncture and grasp the prey, keeping it from wriggling free. Because the most common fossil evidence of cartilaginous fish is teeth, this term is also used for the fossilised teeth themselves.
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Cotton would later be the first to describe in detail the process of harvesting, carving and insetting an anterior costal cartilage graft along with his success using this technique in 11 children after moving to Cincinnati. In 1973, Crysdale visited Grahne in Helsinki, Finland, to observe an anterior-posterior cricoid split with stent placement and was the first to perform this procedure in a child in North America. A search for less morbid sources of cartilage for anterior cricoid augmentation in neonates allowed Park and Forte (1999) to demonstrate that bilateral cartilaginous grafts could be harvested from the superior aspect of the thyroid cartilage in kittens without airway compromise. Success using this technique was later demonstrated in 2001 by Forte, Chang, and Papsin in a series of 17 children.
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Specifically, the age and maturity of bone can be determined by its state of ossification, the age-related process whereby certain cartilaginous and soft tissue structures are transformed into bone. The condition of epiphyseal plates (growth plates) at the ends of the long bones (which includes those of the arms, hands, legs and feet) is another measurement of bone age. The evaluation of both ossification and the state of growth plates in children is often reached through radiography (X-rays) of the carpals (bones of the hand and wrist). In opsismodysplasia, the process of ossification in long bones can be disrupted by a failure of ossification centers (a center of organization in long bones, where cartilage cells designated to await and undergo ossification gather and align in rows) to form.
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A: Chondrocyte with constitutionally active FGFR3 that down-regulates its development via the MAPK/ERK pathway B: Vosoritide (BMN 111) blocks this mechanism by binding to the atrial natriuretic peptide receptor B (NPR-B), which subsequently inhibits the MAPK/ERK pathway at the RAF-1 protein. Fibroblast growth factor receptor 3 (FGFR3) is a receptor that normally down-regulates cartilage and bone growth when activated by one of the proteins known as acidic and basic fibroblast growth factor. It does so by inhibiting the development (cell proliferation and differentiation) of chondrocytes, the cells that produce and maintain the cartilaginous matrix which is also necessary for bone growth. Children with achondroplasia have one of several possible FGFR3 mutations resulting in constitutional (permanent) activity of this receptor, resulting in overall reduced chondrocyte activity and thus bone growth.
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Leucadendron coniferum is an evergreen, dioecious shrub or small tree of up to 4 m (13 ft) high, that develops from a single main stem near the ground. The branches are slightly grooved lengthways and initially may have some rusty hairs pressed against its surface, while later only some powdery hairs remain. The leaves are cartilaginous in consistency, hairless or with some soft hairs, linear inverted lance-shaped, 3.2–6.4 cm (1¼–2½ in) long and 3–5 mm (0.12–020 in) wide, ending at the tip in a rather long and sharp extension of the midvein, the surface hairless or slightly softly hairy. The male flower heads are surrounded by an involucte of few yellow leaves that gradually become shorter and broadened at the base closer to the head.
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Each flower head of 2–3½ cm (0.8–1.4 in) in diameter, is subtended by an initially cup-shaped involucre of narrow, strongly overlapping, woolly, rubbery (or cartilaginous) bracts of with a pointy tip with tufts of long, fine hairs. The individual flower bud is a straight, pale green, 1½–1¾ cm (0.60–0.67 in) long tube, brown opposite the anthers, set with long straight silky hairs. When the flower opens, a tube of ½ cm (0.2 in) long remains, while the four lobes curl back when the flower opens, which are initially cream and later get flushed pink. The style is 21–25 mm (0.83-0.98 in) long, is narrower towards the tip and slightly bend towards the center of the flower head, pale at the base and carmine pink towards the tip.
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With a molecular weight of only 12–15 kDa, single-domain antibodies are much smaller than common antibodies (150–160 kDa) which are composed of two heavy protein chains and two light chains, and even smaller than Fab fragments (~50 kDa, one light chain and half a heavy chain) and single-chain variable fragments (~25 kDa, two variable domains, one from a light and one from a heavy chain). The first single-domain antibodies were engineered from heavy-chain antibodies found in camelids; these are called VHH fragments. Cartilaginous fishes also have heavy-chain antibodies (IgNAR, 'immunoglobulin new antigen receptor'), from which single-domain antibodies called VNAR fragments can be obtained. An alternative approach is to split the dimeric variable domains from common immunoglobulin G (IgG) from humans or mice into monomers.
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Towards the tip, there are five to fourteen blunt, reddish, thickened teeth. The globe-shaped flower heads are about 3 cm (1¼ in) in diameter, sit on a stalk of 1½–3 cm (⅝–1¼ in) long, with three to six together near the end of the branches. Each flower head is subtended by an involucre consisting of ovate bracts with a pointy tip of ¾–1 cm (0.28–0.40 in) that are cartilaginous, thickly covered with densely matted woolly hairs and with a tuft of very short straight hairs at the tip, tightly overlapping, pressed against the underside of the flower head. The common base of the flowers in the same head is somewhat variable in shape, skewed cone-shaped to egg-shaped, 5–8 mm (0.20–0.32 in) long and about 5 mm wide.
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Fractures and dislocations were very uncommon in Pacatnamu, but the archaeologists found two examples of previously healed fractures, one case of multiple unhealed fractures and one case of a severe spinal injury, it was a skeleton belonging to a middle aged woman whose spine fractured at a 90 degree angle they stabilized the fracture and kept her at that angle for the rest of her life. Her knees showed some signs of stress and the archaeologists agree she continued to move around and function after the injury. There was also one case of an extensive injury to an adult males left eye; it is likely he lost the use of this eye in response to the injury or infection. (Donnan and Cock 1986) The archaeologists found two cases of tumors both were most likely benign and cartilaginous in nature.
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In humans, the cartilaginous bar of the mandibular arch is formed by what are known as Meckel’s cartilages (right and left) also known as Meckelian cartilages; above this the incus and malleus are developed. Meckel's cartilage arises from the first pharyngeal arch. The dorsal end of each cartilage is connected with the ear-capsule and is ossified to form the malleus; the ventral ends meet each other in the region of the symphysis menti, and are usually regarded as undergoing ossification to form that portion of the mandible which contains the incisor teeth. The intervening part of the cartilage disappears; the portion immediately adjacent to the malleus is replaced by fibrous membrane, which constitutes the sphenomandibular ligament, while from the connective tissue covering the remainder of the cartilage the greater part of the mandible is ossified.
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Cartorhynchus may have used its flippers in a manner akin to juvenile sea turtles Cartorhynchus had poorly-ossified limbs in spite of its well-ossified skull and vertebrae. However, Motani and colleagues suggested in 2014 that it was still an adult because many early-diverging members of marine reptile lineages have poorly-ossified limbs through paedomorphosis (the retention of immature traits into adulthood), although they did not completely reject the possibility that it was a juvenile due to the existence of only one specimen. In the case of Cartorhynchus, Motani and colleagues proposed that the large, flipper-like forelimbs would have enabled it to move on land, thus making it amphibious. The extensive cartilage at the wrist joint would have allowed the flipper to bend without an elbow; juvenile sea turtles have similarly cartilaginous flippers that they use to move on land.
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In addition to the connection between the stylohyal bone and the tympanic bone as being an indicator of laryngeally echolocating microbats, another definitive marker is the presence of a flattened and expanded stylohyal bone at the cranial end. Microbats that laryngeally echolocate must be able to distinguish between the differences of the pulse that they produce and the returning echo that follows by being able to process and understand the ultrasonic waves at a neuronal level, in order to accurately obtain information about their surrounding environment and orientation in it. The connection between the stylohyal bone and the tympanic bone enables the bat to neurally register the outgoing and incoming ultrasonic waves produced by the larynx. Furthermore, the stylohyal bones connect the larynx to the tympanic bones via a cartilaginous or fibrous connection (depending on the species of bat).
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This is the highest figure thus far measured from any shark, though it also reflects the concentration of force at the tooth tip. Dense aggregations of young sharks, forming in response to feeding opportunities, have been documented in the Indian Ocean. The known diet of the dusky shark encompasses pelagic fishes, including herring and anchovies, tuna and mackerel, billfish, jacks, needlefish and flyingfish, threadfins, hairtails, lancetfish, and lanternfish; demersal fishes, including mullets, porgies, grunts, and flatheads, eels, lizardfish, cusk eels, gurnards, and flatfish; reef fishes, including barracudas, goatfish, spadefish, groupers, scorpionfish, and porcupinefish; cartilaginous fishes, including dogfish, sawsharks, angel sharks, catsharks, thresher sharks, smoothhounds, smaller requiem sharks, sawfish, guitarfish, skates, stingrays, and butterfly rays; and invertebrates, including cephalopods, decapod crustaceans, barnacles, and sea stars. Very rarely, the largest dusky sharks may also consume sea turtles, marine mammals (mainly as carrion), and human refuse.
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Egg Mountain was discovered in 1977 by Marion Brandvold, owner of the Trex Agate Rock Shop in Bynum, Montana, who discovered the bones of juvenile dinosaurs at this site. It is a colonial nesting site on the Willow Creek Anticline in the Two Medicine Formation that is famous for its fossil eggs of Maiasaura, which demonstrated for the first time that at least some dinosaurs cared for their young. The eggs were arranged in dug-out earthen nests, each nest about a parent's body length from the next, and baby dinosaurs were also found with skeletons too cartilaginous for them to walk - similar to those of altricial (helpless) baby birds. The parent(s) must then have brought food to the young, and there is plant matter in the nests that may be evidence of either this or for incubation of the eggs.
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Huxley demonstrated that the skull is built up of cartilaginous pieces; Gegenbaur showed that in the lowest (gristly) fishes, where hints of the original vertebrae might be most expected, the skull is an unsegmented gristly brain-box, and that in higher forms, the vertebral nature of the skull cannot be maintained, since many of the bones, notably those along the top of the skull, arise in the skin. In 1858, the physician Ernst Haeckel studied under Gegenbaur at Jena, receiving a doctorate in zoology (after his medical degree), and became a professor at the same institution, the University of Jena (see: Ernst Haeckel). Ernst Haeckel expanded on the ideas of Gegenbaur while advocating the concepts of Charles Darwin. In 1861, he published "Ueber den Bau und die Entwickelung der Wirbelthier-Eier mit partielleer Dotterbildung" ("Proof that the ovum is unicellular in all vertebrates", Arch. Anat. Phys.
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Laparoscopic view of a horse's spleen (the purple and grey mottled organ) In cartilaginous and ray-finned fish, it consists primarily of red pulp and is normally somewhat elongated, as it lies inside the serosal lining of the intestine. In many amphibians, especially frogs, it has the more rounded form and there is often a greater quantity of white pulp.. A study published in 2009 using mice found that the red pulp of the spleen forms a reservoir that contains over half of the body's monocytes. In reptiles, birds, and mammals, white pulp is always relatively plentiful, and in birds and mammals the spleen is typically rounded, but it adjusts its shape somewhat to the arrangement of the surrounding organs. In most vertebrates, the spleen continues to produce red blood cells throughout life; only in mammals this function is lost in middle-aged adults.
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Atlanticopristis (meaning "Atlantic saw") is an extinct genus of sclerorhynchid (a sawfish-like chondrichthyan) that lived during the Middle Cretaceous (Cenomanian) of what is now the Northeast Region of Brazil, between 100.5 and 93.9 million years ago. Fourteen fossil teeth from Atlanticopristis were found in the Alcântara Formation, and referred to the closely related Onchopristis in 2007; a redescription in 2008 by Portuguese paleontologists Manuel Medeiros and Agostinha Pereira assigned it to a new genus containing one species, Atlanticopristis equatorialis. Like all sawfish, it would have had a long snout armed with modified fish scales shaped into "teeth", but Atlanticopristis's teeth had barbs on both sides. Atlanticopristis inhabited fresh to brackish water estuaries near large conifer forests, and lived in the same time and place as many species of bony fish, cartilaginous fish, and lobe finned fish, as well as some crocodilians, and several dinosaurs.
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The flower heads consist of three, rarely four individual flowers and sit in the axils of inconspicuous, ordinary, flat, green leaves. The four to five bracts that tightly enclose the flower heads are orange-yellow, fleshy, lance-shaped with a pointy tip, 1–2½ cm (0.4–1.0 in) long and ½–¾ cm (0.2–0.3 in) wide, the outer hairless, the inner softly hairy at the tip. The bracts that subtend the individual flowers are lance-shaped with a pointy tip, 4–5½ cm (1.6–2.4 in) long and 1½–1½ cm (0.5–0.6 in) wide, hairless at base but felty hairy near the tip. The straight cream-coloured 4-merous perianth is 4½–5 cm (1.8–2.0 in) long. The lower part called tube, that remains merged when the flower is open, is 2–3 mm (0.08–0.12 in) long, cartilaginous, expanded bulb-like near its base and hairless.
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Nyctosaurus shared the sky with the bird Ichthyornis and with Pteranodon longiceps, though the second Niobrara Pteranodon species, P. sternbergi, had disappeared from the fossil record by this point. In the waters of the Western Interior Seaway below swam mosasaurs such as Clidastes, Ectenosaurus, Eonatator, Halisaurus, Platecarpus and Tylosaurus, several remains of the plesiosaurs Dolichorhynchops and Polycotylus, cephalopods like Baculites and Tusoteuthis, and the sea turtles such as Ctenochelys and Toxochelys were also found. Flightless diving birds such as Ichthyornis and Parahesperornis were also known from the fossil site, a wide variety of fish including swordfish-like Protosphyraena, as well as the predatory fishes Pachyrhizodus, Xiphactinus, Ichthyodectes, Gillicus, Leptecodon, Enchodus and Cimolichthys, the filter feeding Bonnerichthys, the dorsal finned Bananogmius, and the cartilaginous fishes Cretolamna, Ptychodus, Rhinobatos and Squalicorax were also found within the formation. Several dinosaur genera were found along with Nyctosaurus remains, these included the nodosaurids Hierosaurus and Niobrarasaurus, as well as the hadrosaur Claosaurus.
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Normally, vibrations of the tympanic membrane (eardrum) elicited by acoustic stimuli are transmitted through the chain of ossicles (malleus, incus, and stapes) in the middle ear to the oval window of the cochlea. Vibrations of the footplate of stapes transmit through the oval window to the perilymph, which in turn causes the endolymph, the basilar membrane, and the organ of Corti to vibrate, activating ultimately the acoustic sensor cells, the inner hair cells of the organ of Corti. The transfer function of this complex mechanical system under physiological conditions is modulated by the action of two small muscles of the middle ear, the tensor tympani, and stapedius. The tensor tympani arises from the cartilaginous portion of the auditory tube and the osseous canal of the sphenoid and, having sharply bent over the extremity of the septum, attaches to the manubrium of the malleus (hammer); its contraction pulls the malleus medially, away from the tympanic membrane, which tenses the membrane.
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Their second pharyngobranchial is greatly elongated posterolaterally away from third pharyngobranchial, which lacks a cartilaginous condyle to articulate with the preceding, but is contacted by the elongated uncinate process of the second epibranchial. Other features include the position of the pelvic fins far back on the body, the fused medial processes of pelvic girdle, and the presence of an adipose fin (which is also typical for the Protacanthopterygii). The larvae of some Aulopiformes are extremely bizarre-looking, with elongated fins, and do not resemble the adult animals. They were not only described as distinct species, but also even separated as genera and finally in a family "Macristiidae" which was allied with various Protacanthopterygii (sensu lato), but the initial assessment - which found "Macristium" to resemble the deepwater lizardfishes (Bathysauridae) in some details - was not far off the mark: "Macristium" species are larvae of Bathysaurus, while the supposed other "macristiids", "Macristiella" species are larvae of the deepsea tripodfish Bathytyphlops.
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A team of Japanese scientists, Tadayoshi Sasaki and Shigeru Kimura from the Tokyo University of Marine Science and Technology, Ikuo Obata from the National Museum of Nature and Science, and Toshio Ikuya from the Atmosphere and Ocean Research Institute at the University of Tokyo, jointly concluded, while the identity of the carcass could not be determined with certainty, the carcass was most likely that of a large shark. On July 28, 1977, the Zuiyō Maru carcass was commented upon in the international science magazine New Scientist. A scientist from the Natural History Museum in London had the same opinion as Bjerring and Persson, that the remains were not from a plesiosaur. The decomposition pattern of a basking shark, whose spine and brain case is relatively highly calcified for a cartilaginous fish, can be expected to produce a similar shape to a plesiosaur; the first parts that fall off during decomposition are the lower jaw, the gill area, and the dorsal and caudal fins.
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The formation is also known for several theropods, including the spinosaurid Baryonyx, the tyrannosauroid Eotyrannus, the dromaeosaurid Ornithodesmus, the compsognathid Aristosuchus as well as the allosauroid Neovenator. Different types of herbivorous dinosaurs like Iguanodon, Polacanthus, Ornithopsis, Mantellisaurus and Hypsilophodon were also found within the fossil site. Some other animals from the formation include the neosuchian Bernissartia, sea turtles such as Helochelydra and Brodiechelys, the cartilaginous fish Hybodus, ray-finned fishes such as Belonostomus, Caturus, Lepidotes and Scheenstia, as well as the mammals Eobaatar, Loxaulax and Yaverlestes. Reconstruction of the skeleton of Ferrodraco on a diagram showing the known material, and based on the related Tropeognathus mesembrinus A few fossils reported from the Toolebuc Formation and Winton Formation are believed to be from some of the most derived ornithocheiromorphs, due to the age of the fossil remains, which dated back to the Albian and Cenomanian stages of the Cretaceous, and some are even believed to belong to the Turonian stage.
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1880 photo of the Berlin specimen, showing leg feathers that were removed subsequently, during preparation As in the wings of modern birds, the flight feathers of Archaeopteryx were somewhat asymmetrical and the tail feathers were rather broad. This implies that the wings and tail were used for lift generation, but it is unclear whether Archaeopteryx was capable of flapping flight or simply a glider. The lack of a bony breastbone suggests that Archaeopteryx was not a very strong flier, but flight muscles might have attached to the thick, boomerang-shaped wishbone, the platelike coracoids, or perhaps, to a cartilaginous sternum. The sideways orientation of the glenoid (shoulder) joint between scapula, coracoid, and humerus—instead of the dorsally angled arrangement found in modern birds—may indicate that Archaeopteryx was unable to lift its wings above its back, a requirement for the upstroke found in modern flapping flight. According to a study by Philip Senter in 2006, Archaeopteryx was indeed unable to use flapping flight as modern birds do, but it may well have used a downstroke-only flap-assisted gliding technique.
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A cartilaginous skeleton and a large liver (filled with low- density lipids) are the mechanical means with which the frilled shark controls and maintains its buoyancy in the deep waters of the ocean. The shark has an open, lateral-line organ system featuring mechanoreceptor hair cells in grooves exposed to the ocean environment; such a basal clade configuration enhances the frilled shark's perception and detection of changes in the movement, the vibration, and the pressure of the surrounding water. Like all animals, the frilled shark is afflicted by parasites, such as the Monorygma tapeworm, the trematoda flatworm, the Otodistomum veliporum, and the Mooleptus rabuka nematode; and by predators, such as other sharks, as indicated by missing tail-tips lost to a hungry attacker. In New Zealand, the Takatika Grit, in the Chatham Islands, yielded frilled-shark, bird, and conifer-cone fossils that dated to the time of the Cretaceous–Paleogene boundary (66.043 ± 0.011 mya) which suggested that the sharks lived inland, in shallow bodies of water far from the ocean.
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The major alar cartilage (greater alar cartilage) (lower lateral cartilage) is a thin, flexible plate, situated immediately below the lateral nasal cartilage, and bent upon itself in such a manner as to form the medial wall and lateral wall of the nostril of its own side. The portion which forms the medial wall (crus mediale) is loosely connected with the corresponding portion of the opposite cartilage, the two forming, together with the thickened integument and subjacent tissue, the nasal septum. The part which forms the lateral wall (crus laterale) is curved to correspond with the ala of the nose; it is oval and flattened, narrow behind, where it is connected with the frontal process of the maxilla by a tough fibrous membrane, in which are found three or four small cartilaginous plates, the lesser alar cartilages (cartilagines alares minores; sesamoid cartilages). Above, it is connected by fibrous tissue to the lateral cartilage and front part of the cartilage of the septum; below, it falls short of the margin of the nostril, the ala being completed by fatty and fibrous tissue covered by skin.
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Everything he found had been covered so quickly that details were exceptionally well preserved, and the fossils as a whole formed a very unusual collection – fish fins and complete fish, tree trunks with amber, fossils in upright rather than squashed flat positions, hundreds or thousands of cartilaginous fully articulated freshwater paddlefish, sturgeon and even saltwater mosasaurs which had ended up on the same mudbank miles inland (only about four fossilized fish were previously known from the entire Hell Creek formation), fragile body parts such as complete and intact tails, ripped from the seafish's bodies and preserved inland in a manner that suggested they were covered almost immediately after death, and – everywhere –millions of tiny spheres of glassy material known as microtektites, the result of tiny splatters of molten material reaching the ground. The microtektites were present and concentrated in the gills of about 50% of the fossilized fish, in amber, and buried in the small pits in the mud which they had made when they contemporaneously impacted. The fish were not bottom feeders. They had breathed in early debris that fell into water, in the seconds or minutes before death.
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Fossil, Royal Ontario Museum Paleontologist William Parks described skeleton ROM 804 in 1926 as Thescelosaurus warreni, which had in 1922 been discovered in what was then called the Edmonton Formation near Rumsey Ferry on the Red Deer River. When found, it consisted of a partial skull missing the beak region, most of the left pectoral girdle (including a suprascapula, a bone more commonly found in lizards, but which is believed to have been present in cartilaginous form in some ornithopods due to the roughened ends of their scapulae), the left arm except the hand, ribs and sternal elements, a damaged left pelvis, right ischium, the left leg except for some toe bones, articulated vertebrae from the back, hip, and tail, and a number of ossified tendons that sheathed the end of the tail. The body of the animal had fallen on its left side, and most of the right side had been destroyed before burial; in addition, the head had been separated from the body, and the neck lost. Parks differentiated the new species from T. neglectus by leg proportions; T. warreni had a longer tibia than femur, and longer toes.
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The hairless leaves are inverted lance-shaped with a wedge-shaped base narrowing to a stalk, the tip cut-off, with three to five stout teeth of 4½–7 cm (1.8–2.8 in) long and 1–2 cm (0.4–0.8 in) wide. The more or less flattened globe-shaped flowerheads of 5–8 cm (2.0–3.2 in) in diameter have a stalk of about 1 cm (0.4 in) long, are usual set individually but sometimes grouped in twos or threes. The common base of the flowers in the same head is broadly cone-shaped, about 1 cm (0.4 in) long and approximately ¾ cm across. The bracts that subtend each flower head are greyish because they are covered with densely matted silky hairs, tightly overlapping and pressed against the flower head, oval with a pointy tip, about 8 mm (0.3 in) long and 5 mm (0.2 in) wide, and cartilaginous in consistency. The bract that subtends each flower individually encloses the perianth at its base, has an extended pointed tip (cuspidate), about 1 cm (0.4 in) long and ½ cm (0.2 in) wide, very densely set with woolly hairs at the base and silky hairy near the tip.
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In subsp. obtusata the leaves are upright, 1–2½ cm (0.4–1.0 in) long and ½–4½ mm (0.02–0.18 in). In subsp. albomontana, the leaves are slightly rising and overlapping along the branches, 2¼–3¾ cm (0.9–1.5 in) long and 2½–5½ mm (0.10–0.22 in) wide. The flower heads are set at the tip of the branches, globe-shaped and 1½–2 cm (0.6–0.8 in) across. The common base of the flowers in the same head is flattened globe-shaped and 3–4 mm in diam. The involucre consists of a single whorl of cartilaginous, overlapping, pointed oval bracts of 6–8 mm (¼–⅓ in) long and 2–4 mm (0.08–0.16 in) wide, the outside of which is are covered with felty to woolly hair, each with a hardened pointy to stretched tip. The pointy, oval bracts subtending the individual flower are 5–7 mm (0.20–0.28 in) long and 2½–3 mm wide, thickly woolly, tightly encircling the foot of the flower. The 4-merous perianth is 1–1½ cm (0.4–0.6 in) long and straight. The lower part, that remains merged when the flower is open, called tube, is hairless and 2–3 mm (0.08–0.12 in) long, are somewhat flattened on the four sides.
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