Besides ATP, muscle contraction requires
A) sodium.
B) potassium.
C) calcium.
D) tropomyosin and troponin.

Question

Quizplus · Accepted Answer

Muscle contraction requires calcium in order for it to occur. Calcium binds to troponin, allowing tropomyosin to move and expose the myosin binding sites on actin, which leads to muscle contraction. While sodium and potassium are important for nerve impulse transmission and the resting membrane potential of muscle cells, they are not directly involved in muscle contraction. Tropomyosin and troponin are regulatory proteins involved in muscle contraction, but they cannot initiate the process without the presence of calcium.

Besides ATP, Muscle Contraction Requires