MUSCLE PHYSIOLOGY

Detailed explanation-1: -Globular head of myosin contains an ATPase enzyme that along with CO2+ and mg2+ ions catalyses the breakdown of ATP during muscle contraction.

Detailed explanation-2: -Myosins are molecular motors with essential functions in eukaryotic homeostasis. As actin-activated ATPases, myosins convert the chemical energy derived from the hydrolysis of ATP to mechanical work, which enables them to move along actin filaments.

Detailed explanation-3: -The enzyme at the binding site on myosin is called ATPase. The energy released during ATP hydrolysis changes the angle of the myosin head into a “cocked” position. The myosin head is then in a position for further movement, possessing potential energy, but ADP and Pi are still attached.

Detailed explanation-4: -In addition to binding actin, the myosin heads bind and hydrolyze ATP, which provides the energy to drive filament sliding. This translation of chemical energy to movement is mediated by changes in the shape of myosin resulting from ATP binding.

Detailed explanation-5: -Both muscle actomyosin and myosin have ATPase activity which is activated by Ca2+.