What Are the Four Stages of Aerobic Respiration?

The four stages of aerobic respiration are glycolysis, acetyl-CoA, Krebs cycle and the electron transport chain. Aerobic respiration is the process by which the body produces ATP, an important substance that is needed for the survival of cells.

During the first phase, glycolysis, glucose is broken down in the cytoplasm of the cells. This process creates four molecules of ATP, but only two are truly created because two of them are needed to power the process by which glyceraldehyde-3-phosphate is generated.

After pyruvate has been created as a result of glycolysis, it can be used to help create the acetyl-CoA that is needed to continue the respiration process. The pyruvate turns into two acetyl carbons that mix together with the coenzyme-A in the mitochondria of the cells to create the acetyl-CoA.

The third step of aerobic respiration is where the majority of the chemicals that will be used in the formation of ATP are created. The compounds that are formed during this step include isocitrate, alpha ketoglutarate, succinyl-CoA, succinate, fumarate and malate. One molecule of GTP is produced as a result of this step and is then converted to ATP.

When GTP is formed during the third stage, NADH and FADH2 are also produced. These compounds create 34 units of ATP during the final electron transport stage. In combination with the other units of ATP that were created, aerobic aspiration is completed.