In three A we have the oxidation reduction step. This basically takes place or the isocytrate is oxidized into an intermediate oxylociate. In the process, we reduce the NAD plus coenzyme into NADH and the NADH can then be used by the electron transport chain as we'll discuss in the future lecture. In the second step three B, the oxylote undergoes a decreboxylation step in which we release a carbon dioxide and we produce a five carbon molecule alpha ketoglutrate. Now, let's imagine inside our cell we want to produce ATP molecules. So we have a low energy charge value, we don't have enough ATP and so we want to make sure, or the cell wants to make sure that the citric acid cycle takes place at a high rate.