What is the main component of the thin filaments in muscle fibers and is responsible for muscle contraction?
A)actin
B)myosin
C)actin and myosin
D)nerve and bone

A

Explanation:

The primary component of thin filaments is the actin protein. Two other components of the thin filament are tropomyosin and troponin. Actin has binding sites for myosin attachment. Strands of tropomyosin block the binding sites and prevent actin–myosin interactions when the muscles are at rest.

i think that d. wind is the answer.   i missed the question when i answered a. currents.

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