The tricarboxylic acid (TCA) cycle, also known as the Krebs cycle, is a central metabolic pathway in aerobic respiration within eukaryotic cells. It involves the oxidation of pyruvate to carbon dioxide, releasing energy for ATP synthesis. Acetyl CoA, derived from pyruvate or fatty acids, transfers its acetate group to oxaloacetate, forming citrate. This citrate then undergoes decarboxylation and oxidation, regenerating oxaloacetate and releasing two carbon atoms as CO2 per cycle. This cyclic process is crucial for energy metabolism in most aerobic organisms.