Answer:
During cellular respiration, a glucose molecule is gradually broken down into carbon dioxide and water. Along the way, ATP is produced directly in the reactions that transform glucose. However, more ATP is later produced in a process called oxidative phosphorylation.
The body needs to maintain the amount of oxygen that reaches our cells. If we exercise a lot, our breathing rate increases. More oxygen enables our cells to <span>more quickly respire aerobically, so that our muscles can contract more rapidly.
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