* Glycolysis: This process breaks down one glucose molecule into two pyruvate molecules. It produces a net gain of 2 ATP and 2 NADH molecules.
* Krebs Cycle: This cycle takes place in the mitochondria and processes each pyruvate molecule (from glycolysis) into carbon dioxide. It generates 1 ATP, 3 NADH, and 1 FADH2 per pyruvate molecule. Since glycolysis produces two pyruvate molecules, the Krebs cycle produces 2 ATP, 6 NADH, and 2 FADH2 per glucose molecule.
Furthermore:
* The NADH and FADH2 produced by both glycolysis and the Krebs cycle are used in the electron transport chain to generate a much larger amount of ATP (around 34 ATP molecules per glucose molecule).
In summary:
* Glycolysis: Produces a net gain of 2 ATP and 2 NADH
* Krebs Cycle: Produces 2 ATP, 6 NADH, and 2 FADH2
* Electron Transport Chain: Uses NADH and FADH2 to generate ~34 ATP
Therefore, the Krebs cycle, along with the electron transport chain, is responsible for the vast majority of ATP production during cellular respiration.
