What happens during anaerobic cellular respiration?

Anaerobic respiration refers to the enzymatic breakdown of sugar for energy in the absence of oxygen. Most cells in the human body can perform this, at least for short periods of time. One molecule of glucose metabolized anaerobically to pyruvate yields to molecules and adenosine triphosphate. this is a low yield compared to aerobic cellular respiration, in which 36 ATP molecules are generated for each glucose molecule metabolized.  
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