List out any six general features of cartilaginous fishes

animal-kingdom
cbse

#1

Features of cartilaginous fishes
(i) Cartilaginous endoskeleton is present,
(ii) These are mostly marine, poikilothermic animals.
(iii) Notochord is persistent throughout life,
(iv) Placoid scales are present.
(v) Heart is two chambered with one auricle and one ventrical. .
(vi) Tail fin is always heterocercal.