Which of the following describes the function of tropomyosin in a relaxed muscle fiber?
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Correct answer: It blocks the myosin-binding sites on the actin filaments
In a resting muscle, tropomyosin is positioned over the active sites of the G-actin subunits. This prevents the myosin heads from forming cross-bridges until a calcium signal shifts the tropomyosin-troponin complex away.
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