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Statements A-bands of the muscle are d...

Statements
A-bands of the muscle are dark and contain myosin
I-band are the light bands and contain action
During muscle contration the A-band contracts
The part between the two Z-lines is called as saromere
The central part of thin filament, not over-lapped by thick filament is called H-zone of the above statements.

A

A,C,E are correct while, B,D are incorrect

B

A,B,C and E are correct while D is incorrect

C

A,B and D are correct while C and E are incorrect

D

A,B and C are correct while D and E are incorrect

Text Solution

AI Generated Solution

The correct Answer is:
To analyze the statements regarding muscle structure and contraction, let's evaluate each statement step by step. ### Step-by-Step Solution: 1. **Statement A**: "A-bands of the muscle are dark and contain myosin." - **Analysis**: A-bands are indeed the dark bands in muscle fibers and primarily consist of thick filaments, which are made of myosin. - **Conclusion**: This statement is **correct**. 2. **Statement B**: "I-bands are the light bands and contain actin." - **Analysis**: I-bands are the light bands in muscle fibers and primarily consist of thin filaments, which are made of actin. - **Conclusion**: This statement is **correct**. 3. **Statement C**: "During muscle contraction the A-band contracts." - **Analysis**: The A-band does not change in length during muscle contraction; rather, it remains the same length while the I-bands shorten as the thin filaments slide over the thick filaments. - **Conclusion**: This statement is **incorrect**. 4. **Statement D**: "The part between the two Z-lines is called a sarcomere." - **Analysis**: The sarcomere is defined as the segment of a myofibril between two Z-lines, and it is the basic contractile unit of muscle tissue. - **Conclusion**: This statement is **correct**. 5. **Statement E**: "The central part of the thin filament, not overlapped by thick filament, is called the H-zone." - **Analysis**: The H-zone is the region within the A-band where there is only thick filament and no overlap with thin filaments. Therefore, the statement incorrectly describes the H-zone as part of the thin filament. - **Conclusion**: This statement is **incorrect**. ### Summary of Statements: - **Correct Statements**: A, B, D - **Incorrect Statements**: C, E ### Final Answer: The correct statements are A, B, and D. The incorrect statements are C and E. ---
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