How is the lack of oxygen related to the lack of energy?

Answer:
oxygen makes energy in animals. when there is a lack of oxygen in the body, cell respiration stops, and ferminantation begins; this is hwere the cell uses carbon dioxide for energy. this is a temporary fix only, though. it also secretes an acid into your muscles; that's what causes cramps. then, if oxygen gets cut off completely, the cells can no longer use ferminentation and the creature dies.
First answer by Genius423. Last edit by Genius423. Contributor trust: 2 [recommend contributor recommended]. Question popularity: 0 [recommend question].