Question

Term ‘Agnatha’ refers to

• A. Jaw-less fishes
• B. Bony fishes
• C. Cartilaginous fishes
• D. None of these

Answer 1

The correct option is A

Jaw-less fishes

The correct option is A

Explanation of correct option:

1. Agnatha refers to the group of jaw-less fishes.
2. Class Agnatha consists of an ancient group of animals similar to fishes.
3. The agnathans lack jaws and paired fins, having a circular toothed mouth that helps in sucking the blood of their victim.

Explanation of incorrect options:

Option B: Bony fishes(Osteichthyes) are a group of fishes that have a skeleton made up of bones and have true jaws.

Option C: Cartilaginous fishes(Chondrichthyes) have skeletons composed of cartilage.

Final answer: Agnatha refers to Jawless fishes.