Now the only difference between these two enzymes is the fact that glycogen synthase B is simply the phosphorylated version of glycogen synthase A. Now glycogen synthase A always exists in the fully active form. Now glycogen synthase B is predominantly in the inactive form but under certain molecules. So certain molecules that we'll talk about in just a moment can actually act as allosteric activators of glycogen synthase B. And by binding to glycogen synthase B they can actually make it an active molecule. Now to go from glycogen synthase E the fully active molecule that basically stimulates glycogen synthesis into glycogen synthase B the inactive molecule we have to actually use ATP molecules to phosphorylate glycogen synthase A.