MUSCLE PHYSIOLOGY

Detailed explanation-1: -These changes are explained by the actin and myosin filaments sliding past one another, so that the actin filaments move into the A band and H zone. Muscle contraction thus results from an interaction between the actin and myosin filaments that generates their movement relative to one another.

Detailed explanation-2: -ATP and Muscle Contraction 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: -In muscle contraction, the actin filaments slide along the myosin filaments. This is driven by the heads of the myosin molecules, which bind to actin and, in a sequence of binding and release movements, ‘walk’ along the actin filament.

Detailed explanation-4: -Control of Muscle Tension Neural control initiates the formation of actin–myosin cross-bridges, leading to the sarcomere shortening involved in muscle contraction. These contractions extend from the muscle fiber through connective tissue to pull on bones, causing skeletal movement.

Detailed explanation-5: -When a sarcomere contracts, myosin heads attach to actin to form cross-bridges. Then, the thin filaments slide over the thick filaments as the heads pull the actin. This results in sarcomere shortening, creating the tension of the muscle contraction.