Which of the following correctly describes the sequence of events in excitation–contraction coupling in skeletal muscle, from membrane excitation to force generation?
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Correct answer: Action potential → T-tubule depolarization → Ca²⁺ release → cross-bridge cycling
The correct sequence: motor neuron triggers action potential → AP travels along sarcolemma and T-tubules → depolarization activates DHPR-RyR → SR releases Ca²⁺ → Ca²⁺ binds troponin → cross-bridge cycling begins.
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