Another name for the Krebs cycle is the citric acid cycle. The Krebs cycle is also referred to as the tricarboxylic acid cycle.
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.