Cellular (aerobic) respiration is the harvesting of energy from carbohydrates, and comprises two stages.

  1. Glycolysis occurs in the cytoplasm to break down glucose.

  2. Krebs cycle occurs in mitochondria, where oxygen acts as the final acceptor of high-energy electrons.
The reactants are glucose and oxygen, and products are carbon dioxide, water, and ATP.

Heat is also release in this process.