How does an increase in intracellular Ca²⁺ concentration lead to force generation in muscle fibers?
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Correct answer: By shifting troponin–tropomyosin to expose actin's binding sites
Elevated Ca²⁺ binds to troponin, shifting troponin–tropomyosin and unmasking actin binding sites; myosin heads can then bind actin and perform the power stroke, generating force.
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