The tricarboxylic acid cycle
(TCA cycle) is not merely an extension of glycolysis. It is the
central metabolic pathway in cellular respiration. Intermediates are
fed into the cycle from the catabolism of carbohydrates, fats, and
In the TCA cycle, a series of
eight reactions oxidize acetyl residues to carbon dioxide. These
oxidation reactions release energy thats captured and used to
synthesize ATP. This is the big pay-off in aerobic metabolism.
Enough energy is released to synthesize 1012 molecules of ATP!
In this Lesson, well study
the reactions of the TCA cycle in detail. Well also see how this
pathway is regulated and transfers energy.