Question

Which among the following is incorrect about Agnatha?

(a) These are also called as jawless fishes

(b) Scales and fins are present

(c) They adopt parasitic mode of nutrition

(d) They have a circular mouth that acts as sucker

I have been asked this question in an online quiz.

My question is based upon Classification of Animal Kingdom into Different Phylum-2 in portion Animal Kingdom of Biology – Class 11

Answer 1

Right choice is (b) Scales and fins are present

Easiest explanation: Agnatha are also called as jawless fishes. Scales and fins are absent. They adopt parasitic mode of nutrition. Their circular mouth acts as sucker. They are aquatic and most of them are extinct. The only class that exists in this super-class is cyclostomata.