Given below are two statements: one is labelled as Assertion A and other is labelled as Reason R. Assertion A: Endometrium is necessary for implantation of blastocyst. Reason R: In the absence of fertilization, the corpus luteum degenerates that causes disintegration of endometrium. In the light of the above statements, choose the correct answer from the options given below: (NEET 2023)
Answer: (B) (b) Both A and R are true but R is NOT the correct explanation of A.. Answer: (b) Both A and R are true but R is NOT the correct explanation of A.
- A.(a) Both A and R are true and R is the correct explanation of A.
- B.(b) Both A and R are true but R is NOT the correct explanation of A.✓
- C.(c) A is true but R is false.
- D.(d) A is false but It is true.
Correct Answer
(B) (b) Both A and R are true but R is NOT the correct explanation of A.
Solution & Explanation
Answer: (b) Both A and R are true but R is NOT the correct explanation of A. Solution: Assertion A is true — the endometrium (maintained by corpus-luteum progesterone) is necessary for implantation of the blastocyst. Reason R is also true — in the absence of fertilisation the corpus luteum degenerates, causing disintegration of the endometrium leading to menstruation. However R explains why the endometrium breaks down when there is no fertilisation, not why it is required for implantation, so R is not the correct explanation of A. NCERT Reference: Ch 2, p.35, line 16 — "of fertilisation, the corpus luteum degenerates. This causes disintegration"