The Krebs cycle starts with the pyruvate produced during glycolysis. Part of the pyruvate is used to form acetyl-CoA. This reaction also produces carbon dioxide and a molecule of NADH. The acetyl-CoA combines with oxaloacetic acid to produce citric acid.
The cycle continues as a series of chemical reactions occur. Each reaction is catalyzed by an enzyme. The Krebs cycle produces high-energy molecules of ATP and NADH as well as carbon dioxide and FADH2, giving organisms the energy they need to power other chemical reactions.Learn more about Acids & Bases