So it takes place this way and this reverse reaction doesn't actually take place, at least not at a very high rate. And that leads us directly into number seven. So if the process of asphorylation is to actually be a convenient process, we have to actually be able to reverse this process. Because if, asphorylation let's say, turns on a proteins activity, we have to be able to basically turn off the activity of that enzyme by for instance, removing that phosphoryl group. But as I mentioned just a moment ago, this process as shown here, because this is so much more thermodynamically stable than the reactants, this process is essentially a one way reaction. So the question is how can we actually reverse this process?