The binding of calcium to the troponin complex
A)disrupts cross-bridges,allowing filaments to slide past each other.
B)allows tropomyosin to bind actin.
C)opens ion channels,allowing sodium to rush into the muscle cells.
D)causes tropomyosin to shift position,exposing myosin bind sites on actin.

Question

Quizplus · Accepted Answer

The binding of calcium to the troponin complex causes a conformational change that shifts the position of tropomyosin, exposing myosin binding sites on actin. This allows for the formation of cross-bridges between actin and myosin, leading to muscle contraction.

The Binding of Calcium to the Troponin Complex