Question

Muscle contraction uses energy from hydrolysis of ATP. After ATP binds to a myosin head, it is hydrolyzed to ADP and Pi. What happens after the bound Pi is released?

Answer 1

After the bound Pi is released, a new ATP molecule attaches to the myosin head and causes the cross-bridge to detach. ATP hydrolysis releases energy that changes the angle of the myosin head and prepares it for further movement.

Step-by-step explanation:

After the bound Pi is released, a new molecule of ATP attaches to the myosin head, causing the cross-bridge between myosin and actin to detach. During this process, the ATP is hydrolyzed to ADP and inorganic phosphate, P₁, by the intrinsic ATPase activity of myosin. The energy released during ATP hydrolysis changes the angle of the myosin head into a cocked position, preparing it for further movement.