Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R) Assertion (A): All vertebrates are chordates but all chordates are not vertebrates. Reason (R): Notochord is replaced by vertebral column in the adult vertebrates. In the light of the above statements, choose the most appropriate answer from the options given below:
(A) is False but (R) is True.
Both (A) and (R) are True and (R) correctly explains (A).
Both (A) and (R) are True and (R) does not correctly explain (A).
(A) is True but (R) is False.
members of the subphylum Vertebrata possess a notochord during the embryonic period. This notochord is replaced by a cartilaginous or bony vertebral column in the adult. The text explicitly states, 'Thus all vertebrates are chordates but all chordates are not vertebrates.' This confirms that both statements are true and the replacement of the notochord by the vertebral column (which defines vertebrates) explains why they are a subset of chordates (who possess a notochord at some stage) but distinct from protochordates.
Join thousands of students and practice with AI-generated mock tests.