Cellular respiration

Cellular respiration is the process by which cells convert glucose and oxygen into energy, carbon dioxide, and water. This energy is stored in the form of adenosine triphosphate (ATP), which cells use to perform various functions. The process can be divided into three main stages:

1. Glycolysis: This occurs in the cytoplasm and breaks down glucose into two molecules of pyruvate, producing a small amount of ATP and NADH.
2. Krebs Cycle (Citric Acid Cycle): This takes place in the mitochondria, where pyruvate is further broken down, releasing carbon dioxide and transferring energy to NADH and FADH2.
3. Electron Transport Chain: Also in the mitochondria, this stage uses the energy from NADH and FADH2 to produce a large amount of ATP, with oxygen acting as the final electron acceptor to form water.

This process is essential for the survival of aerobic organisms, as it provides the energy needed for cellular activities.