Ques. 1NEET (UG) 2022
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the most appropriate answer from the options given below:
- Both (A) and (R) are correct and (R) is the correct explanation of (A)
- Both (A) and (R) are correct but (R) is not the correct explanation of (A)
- (A) is correct but (R) is not correct
- (A) is not correct but (R) is correct
Answer
(1) Both (A) and (R) are correct and (R) is the correct explanation of (A)
Solution
As per NCERT, the members of subphylum Vertebrata possess a notochord during the embryonic period; the notochord is replaced by a cartilaginous or bony vertebral column in the adult. Thus all vertebrates are chordates but all chordates are not vertebrates.
∴ Both (A) and (R) are correct, and (R) explains (A): urochordates and cephalochordates keep the notochord and never form a vertebral column.
Answer: (1)