And what protein phosphatases do is they use a water molecule to basically remove this group and produce reform this enzyme that now contains this original residue that we basically had right over there. So these are the seven reasons for why phosphorylation is a very effective and a very convenient process. So again, it produces a residue that is modified and contains a net negative charge. And that's precisely what gives it a potential to form many hydrogen bonds and that allows it to actually interact in a much more stabilizing fashion with that substrate molecule. Number three is these protein kinases can easily adjust the rate at which the reaction takes place and the rate really depends on the physiological conditions found inside the cell. Number four is we have an abundance of these high energy ATP molecules that exist inside our cells until we can quickly and effectively use them to actually transfer those phosphoryl groups.