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What is Which of the following decreases in length during the contraction of a skeletal muscle fiber? and explain in detail?
The physical lengths of the actin and myosin filaments do not change during contraction. Therefore, the A band, which is composed of myosin filaments, does not change either. The distance between Z disks decreases, but the Z disks themselves do not change. Only the I band decreases in length as the muscle contracts.