What is the process of cellular respiration?

Cellular respiration is the process by which cells convert nutrients into energy in the form of adenosine triphosphate (ATP), which can then be used for various cellular activities. It is a complex series of reactions that occurs in three main stages: glycolysis, the Krebs cycle, and oxidative phosphorylation.

The first stage, glycolysis, occurs in the cytoplasm and breaks down glucose into two molecules of pyruvate. This process generates a small amount of ATP and NADH, which is an energy-rich molecule that carries electrons to the next stage of cellular respiration.

The second stage, the Krebs cycle, takes place in the mitochondria and further breaks down pyruvate into carbon dioxide, generating more ATP and NADH.

The final stage, oxidative phosphorylation, occurs in the mitochondria and is where the majority of ATP is generated. NADH molecules from the first two stages donate electrons to a series of proteins called the electron transport chain, which creates a gradient of protons across the mitochondrial membrane. This gradient drives the production of ATP through a process called chemiosmosis.

Overall, cellular respiration is a crucial process for all living organisms that require energy to carry out their functions. It plays a vital role in providing energy to the body for various activities such as movement, growth, and repair of tissues.