Question

Identify different regions in the structure of myofibril

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• A. 1. Z disc 2. H zone 3. M line 4. A band 5. I band
• B. 1. Z disc 2. H zone 3. I band 4. A band 5. M line
• C. 1. Z disc 2. H zone 3. M line 4. I band 5. A band
• D. 1. Z disc 2. M line 3. H zone 4. A band 5. I band

Answer 1

The correct option is B

1. Z disc 2. H zone 3. I band 4. A band 5. M line

Each sarcomere is limited by 2 Z discs.

The thick filaments produce the dark A band.

The thin filaments extend in each direction from the Z disk. Where they do not overlap the thick filaments, they create the light I band.

The H zone is that portion of the A band where the thick and thin filaments do not overlap.

The M line runs through the exact center of the sarcomere.