Why is it essential that the regulatory mechanisms that activate glycogen synthesis also deactivate glycogen phosphorylase? (select all that apply.) if this were not the case, a futile cycle would consume atp needlessly. the substrate used in glycogen synthesis can also bind to glycogen phosphorylase, forming an unreactive enzyme-substrate complex. such a regulatory mechanism prevents the simultaneous addition and removal of glucose monomers, preventing unnecessary reactions. without these regulatory mechanisms, both processes would run at full speed, thus inhibiting glycolysis?