Question

What tells a muscle when to contract?

Answer 1

The nervous system transfers the impulse (instruction) from the brain or spinal cord to contract or relax.

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Answer 2

Answer:

nerve cells gives the impulses to muscles when to contract and when to relax..... and also there are three types of nerve cells:-

1. sensory nerve
2. motor nerve
3. associated nerve

hope u hv understood........

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