So it's called oxidoreductase because we have oxidation reduction reactions taking place. So what exactly is the purpose of protein complex Number One? Well, NADH Dehydrogenase basically accepts the electrons from NADH molecules produced in glycolysis, pyruvate carboxylation and the citric acid cycle. So let's imagine that our NADH is produced in the citric acid cycle and then that NADH travels to protein complex number one and it gives the two electrons to protein complex number one. Now, when it donates those two electrons, those two electrons go onto a molecule known as Flavin mononucleotide, or FMN. So we reduce FMM, which is basically a group that is found on protein complex number one.