So we have this special substrate molecule that when reacts with the serene inside the active side, it produces a product that has a certain color to it. And we can essentially monitor the color change and the absorbance of light as we produce that particular product. So if we take a look at the following graph the y axis is the absorbance of light of that product produced when the substrate is catalyzed by the active side and the x axis is basically the reaction progress. So at the zero point at time zero we basically take our mixture of that special substrate and we mix it in with our enzyme and now our reaction begins and notice what kind of curve we actually produce. So we see that initially we have a very steep slope, a very large slope and then the slope begins to level off and so here the rate of the reaction is low but here the rate of the reaction is very fast. Now, what exactly does that tell us about the reaction mechanism of Chimetrypsin?