What is the role of tropomyosin in a sarcomere?

A. It is the main protein component of thin myofilaments.
B. It is the main protein component in thick myofilaments.
C. It blocks the active sites on actin filaments in relaxed muscle fibers.
D. It binds to calcium to initiate muscle contraction.
E. It is the main component of elastic filaments.


Answer: C

Anatomy & Physiology

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