And so what that means is for the biological systems, such as our cells, to actually function effectively and efficiently, they have to have a way of actually controlling and regulating the activity and the functionality of enzymes. And one way by which we can actually control the activity of enzymes is by using these special molecules, and in some cases ions, to basically inhibit the activity of these enzymes. And these are known as Enzymatic inhibitors. So once again, in order to function effectively, biological systems must be able to regulate and control the activity and the functionality of enzymes. Special agents we call inhibitors can bind onto enzymes and inhibit or block their activity. So there are two categories of inhibitors.