And all these processes basically work together to ultimately synthesize that glycogen molecule. So, as we discussed in the previous lecture, before we can actually attach a glucose molecule onto a growing polysaccharide chain, we have to activate that glucose molecule. We have to make it much more reactive. And so what we do is we take a glucose one phosphate and we transform it into a urine diphosphate glucose, UDP glucose, and the UDP glucose is much more active. And now an enzyme known as glycogen synthase can actually synthesize an Alpha one four glycocitic bond, attach that glucose onto that elongating chain. Now, the thing about glycogen synthase is it cannot simply begin from scratch.