The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, is a circular loop rotating through eight organic acid intermediates (e.g., citrate, malate, oxaloacetate). This cycle plays a critical role in moving cell energy production forward, because it is the first pathway of the final stage of energy extraction from nutrients, in which carbon units are fully oxidized. The intermediate products formed in this cycle are also used to build molecules including proteins, DNA, and RNA.
