One is formed in step one and the other one is formed in step three. So we have an enzyme called six phosphoglucanate dehydrogenase. Again, it's a dehydrogenase because we're essentially extracting the two H plus ions along with those two electrons which are picked up by this electron carrier molecule. So this enzyme catalyzes the oxidative decarboxylation. So oxidative means we have an oxidation reduction reaction going on where this is oxidized and this is reduced. And we also have a decarboxylation reaction taking place where this carbon number one along with these two oxygen atoms are essentially removed.