Question

Assertion :Characters of cyclostomes show are advanced over Amphioxus. Reason: Cyclostomes have some degenerated characters.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

Following are the characters of colostomies showing an advance over Amphioxus. A distinct head, however may be secondary, a so-called cranium, a more advanced brain, pro and epinephrine kidneys, secondary notochord, vertebrae introduced (lampreys) etc. Cyclostomes also have some particular specialization like tongue apparatus, sucking mouth with horny teeth, sac-liKe gill pouches, separate branchial sac with branchial basket etc. The degenerated characters of colostomies are:

(i) tongue apparatus

(ii) rudimentary paired eyes in hag fishes

(iii) lack of exoskeleton

(iv) reduced liver and lack of gall bladder and bile duct in adult lamprey