During muscle relaxation, cessation of the electrical impulse stops the release of _____ from the sarcoplasmic reticulum.

Question

Quizplus · Accepted Answer

During muscle contraction, the electrical impulse triggers the release of calcium ions from the sarcoplasmic reticulum, which bind to troponin and initiate the sliding of actin and myosin filaments. When the impulse stops and the muscle relaxes, the release of calcium ions also ceases, allowing the tropomyosin to re-cover the binding sites on actin and myosin and preventing further contraction. Therefore, the correct answer is A, calcium.

During Muscle Relaxation, Cessation of the Electrical Impulse Stops the Release