And as we'll see in more detail, those acetyl Cozume molecules are attached onto this sulfidel group. Now, the process by which we actually form fatty acids isn't a very energetically, favorable process. In fact, we have to use ATP molecules to carboxylate, and then the process of decarboxylation releases energy, and that helps drive the fatty acid synthesis process forward. So we see that fatty acid synthesis is driven by the release of carbon dioxide molecules via a decarboxylation step. Now, in addition to this decarboxylation step, we also have reduction steps. And these reduction steps actually utilize reductant molecules.