And now this is high enough in energy to actually react with our ammonia. Now, notice I said ammonia and not Ammonium. Why is that? Well, because the carbon, well, phosphate synthetase uses the ammonia as a substrate and not ammonium. So remember, inside our body we have ammonium that exists in somewhat of an equilibrium with its ammonia. And so Ammonium transforms into ammonia and then that is used as a substrate by carbon, well phosphate synthetase to basically combine this ammonia with this carbon here, kicking off this orthophosphate.