Which molecule blocks the myosin-binding sites by wrapping around the thin filament?
A) actin
B) myosin
C) tropomyosin
D) troponin

Question

Quizplus · Accepted Answer

Tropomyosin is a regulatory protein that blocks the myosin-binding sites on actin filaments during muscle relaxation. When calcium binds to troponin, it causes a conformational change that moves tropomyosin out of the way, allowing myosin to bind to actin and initiate muscle contraction.

Which Molecule Blocks the Myosin-Binding Sites by Wrapping Around the Thin