EVERYDAY SCIENCE

Detailed explanation-1: -Cartilaginous fishes (chondrichthyes) represent the oldest surviving jawed vertebrates and, as the name suggests, have a skeleton made out of cartilage. They include sharks, rays, and skates (elasmobranchii) and chimeras (holocephali).

Detailed explanation-2: -The skeleton of cartilaginous fishes is made up of cartilage. Only the teeth of this species and rarely the vertebrae are calcified. Sharks, skates, chimaeras and rays make up the group of Chondrichthyes.

Detailed explanation-3: -chondrichthyan, (class Chondrichthyes), also called chondrichthian, any member of the diverse group of cartilaginous fishes that includes the sharks, skates, rays, and chimaeras.

Detailed explanation-4: -Chondrichthyes is a class of jawed fishes having a cartilaginous skeleton. The class includes a diverse group of fishes including sharks, rays, skates and chimaeras. They are mostly marine fishes. The other group of fishes are bony fishes, which are included in the class Osteichthyes.