EDAPT Metabolism and Nutrition Practice Test

Under aerobic conditions, pyruvate is converted to acetyl-CoA through a process known as oxidative decarboxylation. This conversion happens in the mitochondria, where pyruvate, a three-carbon compound produced from glycolysis, is transported. During this process, one molecule of carbon dioxide is released, and the remaining two-carbons are combined with coenzyme A to form acetyl-CoA. This step is crucial as acetyl-CoA then enters the Krebs cycle (or citric acid cycle), which is significant for generating ATP through further oxidation.

This pathway operates effectively in the presence of oxygen, indicating that aerobic conditions allow for a more efficient energy production process compared to anaerobic conditions. In contrast, under anaerobic conditions, pyruvate would instead be converted into lactate (in animals) or ethanol and carbon dioxide (in yeast), which are processes associated with fermentation. The conversion to acetyl-CoA highlights the role of aerobic metabolism in energy production and the utilization of pyruvate as a key intermediate in aerobic cellular respiration.