Question

Which statement correctly describes an activity involved in muscle contraction?

A. Myofibrils attach to Z lines.

B. Sarcomeres produce actin and myosin.

C. Myosin heads attach to sites on actin filaments.

D. ATP causes fascicles to contract muscle fibers.

Answer 1

C. Myosin heads attach to sites on actin filaments.
Hope it can help you!

Answer 2

Answer:

C. Myosin heads attach to sites on actin filaments.

Explanation:

Myosin head have ADP and Pi bound to it. The myosin head binds to active site on actin filament to form a cross bridge. Release of inorganic phosphate from myosin head triggers the power stroke during which myosin head pulls the actin filament towards the center of sarcomere. During each power stroke, movement of actin filament towards the center of sarcomere shorten the muscle.