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Assertion: H-zone of 'A' band is a paler...

Assertion: H-zone of 'A' band is a paler zone in relaxed condition of sarcomere
Reason: Only thin filaments occur in the middle of 'A' band relaxed condition of sarcomere

A

if both assertion and reason are true and the reason is correct explanton of Assertion

B

IF both assertion and reason and reason are true but reason is not a correct explanation of assertion

C

IF assertion is true and reason is wrong

D

if both assertion and reason are wrong

Text Solution

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding the Assertion:** - The assertion states that the H-zone of the A band is a paler zone in the relaxed condition of the sarcomere. - In the sarcomere, the A band contains both thick (myosin) and thin (actin) filaments. The H-zone is the region within the A band where only thick filaments are present, which appears paler because it lacks the overlapping thin filaments. 2. **Evaluating the Reason:** - The reason given is that only thin filaments occur in the middle of the A band in the relaxed condition of the sarcomere. - This statement is incorrect. In the A band, both thick and thin filaments are present, and the H-zone specifically contains only thick filaments. 3. **Determining the Truth of the Statements:** - Since the assertion is true (H-zone is indeed paler in relaxed conditions) and the reason is false (thin filaments do not occur in the H-zone), we conclude that the assertion is true while the reason is false. 4. **Choosing the Correct Option:** - Based on the evaluation, the correct option is that the assertion is true and the reason is false. **Final Answer:** - The correct answer is: Assertion is true and Reason is false. ---
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