Biology · Support and Movement
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Which of the following changes occurs when skeletal muscles contract:
- A
I-band shortens only
- B
A-band shortens and Z-lines move apart
- C
I-band shortens and Z-lines come close to each other
- D
Actin filament contracts
The I- band is the region near the Z - disc where we only have the actin filament. As the sarcomere contracts, the actin overlaps with the myosin filament, shortening the I band as well as bringing the Z discs closer to each other.
This option is incorrect.
According to Sliding filament theory, the thin filaments slide past the thick ones so that actin and myosin filaments overlap to a greater degree. Thus the Z-line is brought close together, I-band shortens, and the H zone disappears.
This option is incorrect.
According to Sliding filament theory, the thin filaments slide past the thick ones so that actin and myosin filaments overlap to a greater degree. Thus the Z-line is brought close together, I-band shortens, and the H zone disappears.
According to Sliding filament theory, the thin filaments slide past the thick ones so that actin and myosin filaments overlap to a greater degree. Thus the Z-line is brought close together, I-band shortens, and the H zone disappears.
This option is incorrect.
According to Sliding filament theory, the thin filaments slide past the thick ones so that actin and myosin filaments overlap to a greater degree. Thus the Z-line is brought close together, I-band shortens, and the H zone disappears.
Tagged under Biology · Support and Movement · 2017