What happens to pyruvate when it enters the mitochondria?

When pyruvate enters the mitochondria, it undergoes a conversion into Acetyl CoA. This is a crucial step in cellular respiration, particularly during the process of aerobic metabolism. Acetyl CoA serves as an important substrate for the citric acid cycle (Krebs cycle), where it is further oxidized to produce energy in the form of ATP, carbon dioxide, and electron carriers like NADH and FADH2.

The conversion of pyruvate to Acetyl CoA is facilitated by the pyruvate dehydrogenase complex, which also produces carbon dioxide as a byproduct. This pathway is essential for the efficient production of energy in aerobic conditions, marking the transition from glycolysis (which occurs in the cytoplasm) to the citric acid cycle (which occurs in the mitochondria). Understanding this transformation is key to grasping how cells extract energy from glucose and its metabolites under aerobic conditions.