And so the NAD plus extracts two electrons as well as an H ion, and it forms the NADH. It also releases an H plus ion. So essentially, the NADH molecule grabs this H atom along with the two electrons, and that releases the H plus ion, and that forms a double bond between this oxygen and this carbon. So we ultimately transform the alcohol group into a keto group that contains this carbonyl group shown here. So this molecule is known as the three keto, acyl coenzyme A. So the third step is the second oxidation step in which the hydroxyl group on the third carbon, the beta carbon, is transformed into the keto group in the process that produces a nicotine amine adenine dinucleotide molecule.