General characters of class chondrichthyes species:
• Most of these animals are marine and carnivorous in nature.
• chondrichthyesb is spindle shaped.
• chondrichthyes is a presence of paired fins and median fin. caudal fin is heterocercal.
• chondrichthyes a presence of fin rays in fins.
• The skin is tough which contains placoid scales and mucous glands.
• e is completely made up of cartilage. Hence, they are known as cartilagenous fishes.
• cartilaginous outh is situated on the ventral side. One pair of jaw are present with teeth.
• Teeth are modified placoid scales.
• cartilaginous intestine has a spiral valve,
• chondrichthyes respire through 5 to 7 pairs of gills. The gill slits are separate and do not covered by opeculum. There are absence of accessory respiratory organs.
• The heart is 2-chambered i.e. one auriele and one ventricle. There is presence of sinus venosus and conus arteriosus. Both the portal systems ie renal portal system and hepatic portal system are presence.
• .cartilaginous kidneys are opisthonephrie type. They excrete in the form of urea (ureotelic animals) and there is a cloaca
• The brain has large olfactory lobes and cerebellum. There are 10 pairs of cranial nerves.
• cartilaginous olfactory sacs do not open into the pharynx. The internal ear has 3 semicircular canals. There is presence of lateral line organs.
• chondrichthyes are dioceous animals.
• e.cartilaginous is presence of one pair of gonad. Gonoducts open into cloaca.
• chondrichthyess internal fertilization.
• They are oviparous or ovoviviparous animals and have no metamorphosis
• General character of chondrichthyes. Class chondrichthyes.bony fish.cartilaginous. classification of chondrichthyes.,
• General character of chondrichthyes. Class chondrichthyes.bony fish.cartilaginous. classification of chondrichthyes.,
• General character of chondrichthyes. Class chondrichthyes.bony fish.cartilaginous. classification of chondrichthyes.,
chondrichthyes species
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chondrichthyes species.