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A : Inmosses, second stage of gametophyt...

A : Inmosses, second stage of gametophyte consists of upright, slender axes bearing spirally arranged leaves.
R : This stage of gametophyte consists of sex organs.

A

If the Assertion & Reason are true and the reason is the correct. Explanation of the assertion.

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion.

C

If Assertion is true statement but Reason is false.

D

If both Assertion and Reason are false statements.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion (A) and the reason (R) regarding the gametophyte stage in mosses. ### Step-by-Step Solution: 1. **Understanding the Assertion (A)**: - The assertion states that in mosses, the second stage of the gametophyte consists of upright, slender axes bearing spirally arranged leaves. - In mosses, the gametophyte is the dominant stage of the life cycle, and it has two forms: the protonema (the first stage) and the leafy stage (the second stage). - The leafy stage is characterized by upright, slender structures that bear spirally arranged leaves. This description aligns with the assertion. 2. **Understanding the Reason (R)**: - The reason states that this stage of the gametophyte consists of sex organs. - In mosses, the gametophyte is indeed where the sex organs (antheridia for male and archegonia for female) are located. This is true, as the gametophyte is responsible for producing gametes. 3. **Evaluating the Truth of A and R**: - Both the assertion and the reason are true statements regarding the mosses and their life cycle. - However, we need to determine if the reason is a correct explanation of the assertion. 4. **Analyzing the Relationship**: - The assertion describes the structure of the gametophyte (the leafy stage), while the reason discusses the presence of sex organs. - Although both statements are true, the presence of sex organs does not explain why the second stage of the gametophyte consists of upright, slender axes with spirally arranged leaves. 5. **Conclusion**: - Since both the assertion and reason are true, but the reason does not explain the assertion, the correct answer is that both A and R are true, but R is not the correct explanation of A. ### Final Answer: **Option B**: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.
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