Which structure is the basic contractile unit of skeletal muscle that shortens during contraction?
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Correct answer: Sarcomere
The sarcomere — the segment between two Z-discs — is the functional unit that shortens when muscle contracts, as thin (actin) and thick (myosin) filaments slide past each other.
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More Muscle Physiology and Contraction questions
- According to the sliding filament theory, which of the following occurs during muscle contraction?
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