So what's actually taking place is upon the binding of the substrate molecules into the active sides. The active sides found on the different catalytic trimers basically begin to interact with one another and they cooperate with one another. And that's exactly what shifts entire curve from one side of the equation to the other side of the equation. And this is what we know as the cooperative behavior of Alphaic enzymes such as aspartate transcarbomolase. And this mechanism can be described by using the concerted model which we actually use to describe the behavior of hemoglobin molecules. So based on this model, the activity of this aspartate transcarbomolase is all or nothing.