So in step one in the cytoplasm, NADH produced in glycolysis is oxidized back into NAD. Plus, by reducing dihydroxy acetone phosphate DHAP into glycerol three phosphate g three P. And this reaction allows us to regenerate the energy plus. Needed for the glycolytic pathway and also allows us to actually pass down the electrons onto a molecule that can now move into the intermembrane space of the mitochondria. And this is catalyzed by the cytoplasmic glycerol three phosphate dehydrogenase enzyme. Now, once the g three P actually moves into the intermembrane space of the mitochondria, it is now oxidized back into DHAP by an enzyme that is found on the outer portion of the inner membrane of the mitochondria. And this enzyme, shown here in orange, is actually an isozyme version of this cytoplasmic glycerol three phosphate dehydrogenous enzyme.