Question

Assertion: Smooth muscle fibres do not appear to be striated.
Reason: Striation occurs due to the regular alternate arrangement of thick and thin filaments in the smooth muscle fibre.

• A. If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
• B. If both Assertion and Reason are correct, but Reason is not correct explanation of Assertion.
• C. If Assertion is correct but Reason is incorrect.
• D. If Assertion is incorrect but Reason is correct.

Answer 1

Answer: (C)

Option D:

Assertion statement:

1. Smooth muscles are the only types of muscles that are devoid of any striations.
   
2. Only the cardiac muscles and skeletal muscles are the striated muscles in the system.
   
3. Hence, the assertion statement is true.
   

Reason statement:

1. The striations in the striated muscles are due to alternate arrangement of the thick filaments and the thin filaments present in the smooth muscle fibres. ​
2. Dark regions of the striations are due to thick filaments while the white regions are made up of thin filaments.
   
3. But these striations are not present in the smooth muscles.
   
4. Hence, the reason statement is false.
   

Final Answer: Assertion is correct but Reason is incorrect.