So it extends and elongates the glycogen polymer chain. Now this enzyme enzyme is not only actually used to build up the glycogen chain it is also actually used to control the rate at which glycogen synthesis actually takes place. So we can actually turn off the glycogen synthase enzyme and that in turn turns off the process of glycogenesis. So once again, glycogen synthase catalyzes the elongation of glycogen. It attaches the glucose monuments by forming alpha one four glycocitic bonds. But this important enzyme also happens to be a key regulatory protein in glycogenesis.