MEDICAL PHYSIOLOGY

Detailed explanation-1: -Step 2: ATP binding to the myosin head domain induces a small conformational shift in the actin-binding site that reduces its affinity for actin and causes the myosin head to release the actin filament .

Detailed explanation-2: -The motion of muscle shortening occurs as myosin heads bind to actin and pull the actin inwards. This action requires energy, which is provided by ATP.

Detailed explanation-3: -Answer and Explanation: The correct answer: The process which releases the myosin head to be released from the actin is A. ATP binding myosin. The release of the myosin head from the actin takes place after a power stroke when a contraction process is completed.

Detailed explanation-4: -If thin filaments, which contain actin, tropomyosin, and troponin, are added to purified myosin, the stimulation of the myosin ATPase activity is wholly dependent on the presence of calcium.