What tells a muscle when to contract?

What tells a muscle when to contract?

Explanation:

(1) A message travels from the nervous system to the muscular system, triggering chemical reactions.

(2) The chemical reactions lead to the muscle fibers reorganizing themselves in a way that shortens the muscle--that’s the contraction.

(3) When the nervous system signal is no longer present, the chemical process reverses, and the muscle fibers rearrange again and the muscle relaxes.

The nervous system generates a signal, which triggers a muscle to contract

Explanation:

yes

no

blue is scattered more than other colors because it travels as shorter, smaller waves. this is why we see a blue sky most of the time.