Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R: Assertion A: The first stage of gametophyte in the life cycle of moss is protonema stage. Reason R: Protonema develops directly from spores produced in capsule. In the light of the above statements, choose the most appropriate answer from the options given below:
Answer: (A) Both A and R are correct and R is the correct explanation of A.. Answer: (A) Both A and R are correct and R is the correct explanation of A.
- A.Both A and R are correct and R is the correct explanation of A.✓
- B.Both A and R are correct but R is NOT the correct explanation of A.
- C.A is correct but R is not correct.
- D.A is not correct but R is correct.
Correct Answer
(A) Both A and R are correct and R is the correct explanation of A.
Solution & Explanation
Answer: (A) Both A and R are correct and R is the correct explanation of A. Solution: In a moss the gametophyte is the predominant phase and consists of two stages; the first is the protonema stage (Assertion A is correct). This protonema develops directly from a spore, and the spores are formed after meiosis within the capsule (Reason R is correct). Because the protonema arises precisely from the capsule-borne spores, R correctly explains why protonema is the first gametophytic stage, so the answer is option A. NCERT Reference: Class XI Biology, Plant Kingdom, p.30, lines 10-11 — "The first stage is the protonema stage, which develops directly from a spore."