Which process in cellular respiration involves the conversion of pyruvate into acetyl coenzyme A?

The process in cellular respiration that involves the conversion of pyruvate into acetyl coenzyme A is the transition stage. After glycolysis, which occurs in the cytoplasm and converts glucose into two molecules of pyruvate, the transition stage occurs when those pyruvate molecules are transported into the mitochondria.

During this stage, each pyruvate undergoes a decarboxylation reaction, where a carbon dioxide molecule is removed. This process not only transforms pyruvate into acetyl coenzyme A (acetyl CoA) but also produces NADH from NAD+, which carries high-energy electrons to the electron transport chain later in the cellular respiration process.

The transition stage is crucial as acetyl CoA then enters the Krebs cycle (also known as the citric acid cycle), where it is further processed for energy production. Understanding this conversion highlights how cells efficiently process energy sources to generate ATP, the energy currency of the cell.