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Pyruvate has several possible fates depending on the metabolic conditions of the cell, particularly the availability of oxygen. Under aerobic conditions (presence of oxygen), pyruvate is primarily converted into acetyl-CoA, which enters the citric acid cycle, leading to further ATP production via oxidative phosphorylation. In the absence of oxygen, such as during intense muscle activity or in certain microorganisms, pyruvate can be converted into lactate (lactic acid fermentation) to regenerate NAD+ and allow glycolysis to continue, albeit without a large ATP yield. In some organisms, such as yeast, pyruvate can also be converted into ethanol through alcoholic fermentation, again helping to regenerate NAD+ for glycolysis. Each of these pathways ensures that cells can continue to generate energy under different environmental conditions.
BNO Team
