Final answer:
Pyruvate is oxidized into acetyl CoA during aerobic respiration, where it undergoes a transformation involving CO2 removal and attachment to CoA, before entering the citric acid cycle for further energy production.
Step-by-step explanation:
During aerobic respiration, pyruvate is oxidized into acetyl CoA. This process involves the transport of pyruvate molecules, produced at the end of glycolysis, into the mitochondria of eukaryotic cells. There, a molecule of carbon dioxide (CO2) is removed, yielding an acetyl group which is then attached to coenzyme A (CoA), forming acetyl CoA.
Coenzyme A is derived from vitamin B5, pantothenic acid. The production of acetyl CoA is significant as it delivers the acetyl group derived from pyruvate to the citric acid cycle (Krebs cycle), which is a key pathway in cellular respiration for further catabolism and ATP production. During this transformation, two high-energy electrons are transferred to NAD+, resulting in the formation of NADH which later participates in the electron transport chain for ATP synthesis.