We get tired after exercise because our muscle fibers get tired very quickly. This is due to the major source of energy for the muscle tissue, called adenosine triphosphate, or ATP. As the muscles make use of this supply of energy, they get tired and fatigue.
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is there a picture of it so I can answer
5 ..................................................... Explanation:
In your body to maintain and support the conditions that your cells, tissues,and organs need to function properly. the skin is one of the first defense mechanisms in your immune system.
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