Final answer:
The process by which organisms transfer the chemical bond energy in organic molecules to ATP molecules is called cellular respiration. Cellular respiration involves three main stages: glycolysis, the citric acid cycle, and oxidative phosphorylation.
Step-by-step explanation:
The process by which organisms transfer the chemical bond energy in organic molecules to ATP molecules is called cellular respiration. Cellular respiration is a series of chemical reactions that occur in the cells of organisms, converting glucose and other organic molecules into ATP, carbon dioxide, and water. This process involves three main stages: glycolysis, the citric acid cycle, and oxidative phosphorylation.
During glycolysis, a molecule of glucose is broken down into two molecules of pyruvate, producing a small amount of ATP and electron carriers (NADH). The pyruvate then enters the citric acid cycle, where it is further oxidized, producing more electron carriers (NADH and FADH2) and a small amount of ATP. Finally, in oxidative phosphorylation, the electrons carried by NADH and FADH2 are transferred to the electron transport chain, generating a proton gradient. This gradient is used by ATP synthase to produce ATP.