Which selection best describes the initial event in contract

Which selection best describes the initial event in contraction? Myosin heads bind to the newly exposed myosin-binding sites on actin to form cross bridges. Calcium binds actin to myosin to begin the cross bridge cycle. The myofilaments slide closer together. Tropomyosin binds to myosin heads and actin bridges with tropomyosin.

Solution

Ans). a. Myosin heads binds to the newly exposed myosin- binding sites on the actin to form cross bridges.

Muscle fiber generates tension through the action of actin and myosin cross-bridge cycling.