Question

What are responsible for contraction and relaxation in muscles?

Answer 1

Skeletal muscles are involved in contraction and relaxation. An action potential travels through the motor neuron. The motor neurons are linked to the muscle fibers at the neuromuscular junction. When this nervous signal reaches the neuromuscular junction the neurotransmitter called acetylcholine is released. This neurotransmitter binds to the receptors on the surface of the muscle fiber leading to muscular contraction.

Answer 2

Answer:

About muscles

Explanation:

Skeletal muscles are involved in contraction and relaxation. An action potential travels through the motor neuron. ... This neurotransmitter binds to the receptors on the surface of the muscle fiber leading to muscular contraction. Thus the correct answer is option A.

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