Pyruvic acid is a key organic compound in cellular metabolism. It is produced during the breakdown of glucose through a process called glycolysis, which occurs in the cytoplasm of cells. Pyruvic acid can be converted into various substances, depending on the availability of oxygen, playing a crucial role in energy production. In the presence of oxygen, pyruvic acid is further processed in the Krebs cycle to generate ATP, the energy currency of cells. When oxygen is scarce, it can be converted into lactic acid in animals or ethanol in yeast, allowing cells to continue producing energy under anaerobic conditions.