D. The basic unit of structure and function in all living things.
Answer:
As the cells run out of oxygen they switch to anaerobic respiration, which allows the cell to make small amounts of ATP in the absence of oxygen.
Explanation:
The fatigue in the muscle is due to lactic acid fermentation which occurs during vigorous muscular activity when blood is unable to supply enough oxygen to muscles. The lactic acid accumulates in the muscle causing pain and muscle cramps.
Glucose → Lactic acid + 2ATP
A is the answer because this the only thing that folds
