Overview of Cellular Respiration

Cellular respiration involves the breakdown of organic compounds like glucose to extract energy. This process occurs in three stages: glycolysis (in the cytosol), the citric acid cycle, and oxidative phosphorylation (in mitochondria).

Glycolysis

Glycolysis breaks down one glucose molecule into two pyruvate molecules, resulting in the production of two ATPs and the reduction of NAD+ to NADH.

Citric Acid Cycle

The pyruvate enters the mitochondria and undergoes further modification, leading to the citric acid cycle. Here, additional carbon dioxide is released, two more ATPs are produced, and NADH and FADH2 are generated, capturing most of the energy from glucose.

Oxidative Phosphorylation

This final stage utilizes the electrons from NADH and FADH2 in the electron transport chain. The process requires oxygen, which reacts with electrons and hydrogen ions to form water, resulting in the production of approximately 34 ATP molecules per glucose molecule.

Byproducts

The overall byproducts of cellular respiration are carbon dioxide and water.