Question

Which process must occur for a muscle to be able to relax?

DA
The amount of ATP in the neuromuscular junction must increase.
O B. A nerve must initiate an action potential in the muscle fiber.
O C. Myosin and actin must attach to each other.
O D.
The concentration of calcium in the myofibril must decrease.

Answer 1

Answer: The correct option is D.

The concentration of calcium in the myofibril must decrease.

Step-by-step explanation:

This is because calcium makes myosin, actin and ATP to interact which actually lead to the contraction of muscle fibre.

Relaxation of muscle fibres occurs when the nerves stop stimulating. The result in the pumping of Calcium into the sarcoplasmic reticulum which then cause a break in the link that connect actin and myosin. Actin and myosin return to their unbound state leading to the relaxation of the muscle .