So this is what we form after this step. So the hydroxyl group on the fourth carbon. So if we actually label our carbons, so let's say this is carbon one, carbon two, carbon three, carbon four, carbon five, and carbon six. So this hydroxyl group on the fourth carbon of the terminal glucose residue of the growing poly of the growing polysaccharide chain, basically attacks this carbon here. Carbon one displacing this entire group and that creates that alpha one four glycocitic bond. Now, notice that glycogen synthase only creates alpha one four glycocitic bonds, but we know glycogen also contains alpha one six glycocytic bonds, about every ten glucose residues.