Why Do Human Cells Respire Anaerobically

Why Do Human Cells Respire Anaerobically. Many species of bacteria also respire anaerobically and produce lactic acid as a waste product. They begin to respire anaerobically.

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They begin to respire anaerobically. 21 yeast is able to respire both aerobically and anaerobically. When do our muscle cells respire anaerobically?

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What could be the reason for this? When there is a temporary deficiency of oxygen in the muscle cells; Give two therapies to release muscle cramps. What could be the reason for this?