Cellular respiration primarily produces adenosine triphosphate (ATP) as its main form of energy. This process occurs in living organisms and involves the breakdown of glucose and other substrates in the presence of oxygen.
During cellular respiration, glucose undergoes a series of metabolic pathways: glycolysis, the Krebs cycle, and oxidative phosphorylation. In glycolysis, glucose is broken down into pyruvate, which then enters the Krebs cycle. This cycle further breaks down the pyruvate and releases energy in the form of high-energy electron carriers, such as NADH and FADH2.
The final stage, oxidative phosphorylation, occurs in the mitochondria of the cells. Here, electrons from the electron carriers are transferred through a series of proteins known as the electron transport chain. The energy from these electrons is used to pump protons across the mitochondrial membrane, creating a proton gradient. As protons flow back across the membrane, they drive the synthesis of ATP from adenosine diphosphate (ADP) and inorganic phosphate (Pi) through an enzyme called ATP synthase.
Ultimately, the process of cellular respiration efficiently converts the biochemical energy stored in glucose into usable energy in the form of ATP, which powers various cellular activities necessary for life.