The process by which living organisms break down glucose for energy is known as cellular respiration. This metabolic pathway occurs in the mitochondria of cells and involves a series of biochemical reactions, including glycolysis, the Krebs cycle, and the electron transport chain. Cellular respiration converts glucose and oxygen into carbon dioxide, water, and ATP (adenosine triphosphate), which serves as the primary energy currency of cells. This process is essential for maintaining cellular functions and supporting life.