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Assertion: Prophase is the first stage o...

Assertion: Prophase is the first stage of mitosis which follows S and `G_(1)` phases of interphase.
Reason: Prophase is marked by the intiation of clusters of chromocomes.

A

If both assertion and reason are true and reason is the correct explantion of assertion

B

If both assertion and reason are true but reason is not the correct explnantion of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To analyze the given assertion and reason, we will break down the statements step by step. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that "Prophase is the first stage of mitosis which follows S and G1 phases of interphase." - In the cell cycle, interphase is divided into three phases: G1 (cell growth), S (DNA synthesis), and G2 (preparation for mitosis). - Mitosis (M phase) follows interphase and begins with prophase. 2. **Identifying the Correct Sequence**: - The correct sequence of interphase is G1 → S → G2. - Prophase is indeed the first stage of mitosis, but it follows the G2 phase, not the G1 phase. 3. **Conclusion on the Assertion**: - Therefore, the assertion is **false** because prophase does not follow the G1 phase; it follows the G2 phase. 4. **Understanding the Reason**: - The reason states that "Prophase is marked by the initiation of clusters of chromosomes." - During prophase, chromosomes condense and become visible as distinct entities under a microscope. This is known as chromosomal condensation. 5. **Identifying the Correct Description**: - The statement about prophase being marked by the initiation of clusters of chromosomes is misleading. It is more accurately described as the condensation of chromosomes rather than the initiation of clusters. 6. **Conclusion on the Reason**: - Therefore, the reason is also **false** because it inaccurately describes the events occurring during prophase. 7. **Final Conclusion**: - Since both the assertion and the reason are false, the correct answer is that both the assertion and reason are false. ### Final Answer: Both the assertion and reason are false. ---
To analyze the given assertion and reason, we will break down the statements step by step. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that "Prophase is the first stage of mitosis which follows S and G1 phases of interphase." - In the cell cycle, interphase is divided into three phases: G1 (cell growth), S (DNA synthesis), and G2 (preparation for mitosis). - Mitosis (M phase) follows interphase and begins with prophase. ...
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