And this is precisely what speeds up that particular reaction. In addition, we have those catalytic groups that are responsible for stimulating the breaking of bonds and the forming of bonds. Now, property number three active sites create a microenvironment. So if we look in the following diagram, we have this active side. And what the active side does is when it actually binds onto that substrate, it essentially closes off ever so slightly and it creates this microenvironment that is predominantly nonpolar. In fact, the only time we're going to find water molecules inside the active side is when the water molecule is actually a participant or reactant in that particular chemical reaction.