In: Biology
The FADH2 and NADH molecules are the main cofactor molecules that help in the metabolic energy transactions. They are the intermediates that undergo ETC to produce ATP and also they are also act as oxidising agents in the cells. Normally in a typical cell their concentration is low when compared to the substrate molecules. Hence by this we can state that they rapidly oxidise the substrates and get reduced later rapidly and hence are ready for another round of oxidation - reduction. Hence they are highly reactive compounds undergoing oxidation and reduction at a very rapid rate.
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