what happens when oxygen present
In the absence of oxygen, the pyruvates are fermented into lactate, which recycles NADH into its oxidizing form, NAD+. If oxygen is present, the cell can reap much more energy through the oxidative decarboxylation of pyruvate and the citric acid cycle. Pyruvate at the Crossroads A cell can use the product of glycolysis, pyruvate, in several metabolic pathways besides decarboxylation.