Final answer:
ATP binding to the myosin head is true, causing it to detach from actin and initialize the next cycle of muscle contraction. ATP hydrolysis energizes the myosin head, preparing it for the subsequent power stroke. The cycle continues with ATP binding and hydrolysis playing a vital role.
Step-by-step explanation:
The statement regarding ATP binding to the myosin head during the movement of the Myosin II head on the actin filament is true. When ATP binds to the myosin head, it causes the myosin to detach from the actin filament. This is followed by ATP hydrolysis, which energizes the myosin head, changing it into a high-energy or 'cocked' conformation ready for another cycle of cross-bridge interaction.
During muscle contraction, the cross-bridge cycle begins with the myosin head attached to actin while ADP and inorganic phosphate (Pi) are still bound to myosin, leading to the power stroke. After the stroke occurs and ADP and Pi are released, a new molecule of ATP binds to the myosin head, leading to its detachment from the actin. Consequently, ATP is hydrolyzed, and the myosin head is energized and repositioned for the next cycle of interaction with the actin filament.
The process of ATP binding and hydrolysis and the resulting conformational changes in the myosin head are crucial for muscle contraction and relaxation, forming the basis of the sliding filament theory.