Question

Name the two major groups of fishes based on the composition of endoskeleton.

Answer 1

Fishes are classified based on the composition of their endoskeleton as

i) Cartilaginous fishes (Chondrichthyes)- endoskeleton made of cartilage (e.g. sharks and rays)
ii) Bony fishes (Osteichthyes)- endoskeleton made of bone tissue (e.g. tuna, marlin etc).