Question

Which of the following is absent in shark?

• A. Claspers
• B. Cartilaginous endoskeleton
• C. Placoid scales
• D. Air bladder

Answer 1

The correct option is D Air bladder

A. Claspers are external appendages found in male sharks and rays fishes and are meant for delivering sperms to female.

B. Cartilaginous endoskeleton is made up of cartilage and is present in fishes of class Chondrichthyes.

C. Placoid scales are tiny and tough appendages which cover the skin of rays, sharks and other elasmobranchs.

D. Air bladder or swim bladder is a gas filled organ that enables the fishes to swim and stay constantly at any depth of water without spending any energy.

Sharks belong to class Chondrichthyes and lack air bladder.

So, the correct answer is 'Air bladder'.