The chemical reaction that converts glucose into ATP is called cellular respiration. This process occurs in several stages, including glycolysis, the citric acid cycle (Krebs cycle), and the electron transport chain. Glycolysis, which takes place in the cytoplasm, breaks down glucose into pyruvate, while the citric acid cycle occurs in the mitochondria, where further breakdown yields electron carriers. These carriers then drive the electron transport chain, ultimately producing ATP. Cellular respiration is essential for converting stored energy in glucose into a usable form for cellular activities, playing a critical role in maintaining life.