And protein kinase A actually does two important things. Number one is it creates a pathway that activates glycogen breakdown and it also creates a pathway that essentially deactivates glycogen synthesis. So let's begin by focusing on this pathway here. So protein kinase A in the active form goes on and phosphorylates an enzyme called phosphorylase kinase and that transforms it into the active form. Now, phosphoralase kinase in the active form goes on to activate phosphorate, phosphorase B and that transforms it into the much more active phosphorase A. Remember, phosphorase A exists predominantly in the relaxed state and so it's fully active.