Assertion:Skeletal muscles contraction is due to shortening of sarcomere
Reason:Sarcomere is the functional unit of skeletal muscles

Options

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

Answer

To solve the question regarding the assertion and reason about skeletal muscle contraction and sarcomeres, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Assertion**: The assertion states that "Skeletal muscles contraction is due to shortening of sarcomere." This is true because during muscle contraction, the sarcomeres, which are the basic units of muscle fibers, shorten as the actin and myosin filaments slide past each other.

2. **Understand the Reason**: The reason states that "Sarcomere is the functional unit of skeletal muscles." This is also true. The sarcomere is indeed the smallest contractile unit of muscle tissue and is essential for muscle contraction.

3. **Evaluate the Relationship**: Now we need to determine if the reason correctly explains the assertion. While both statements are true, the reason does not specifically explain why the contraction occurs. The contraction is due to the sliding of actin and myosin filaments, which leads to the shortening of the sarcomere.

4. **Conclusion**: Since both the assertion and reason are true, but the reason does not provide the correct explanation for the assertion, we conclude that the correct option is: "Both assertion and reason are true, but reason is not the correct explanation of assertion."

### Final Answer:
The assertion is true, the reason is true, but the reason does not correctly explain the assertion.

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