Which molecule's activity is directly regulated by the presence and binding of calcium?
A) actin
B) myosin
C) tropomyosin
D) troponin

Question

Quizplus · Accepted Answer

Troponin is a regulatory protein found in muscle fibers that controls the interaction between actin and myosin. The presence and binding of calcium to troponin causes a conformational change in the molecule, which allows the myosin head to bind to actin and initiate muscle contraction.

Which Molecule's Activity Is Directly Regulated by the Presence and Binding