And notice we have this line and this curve will never actually cross this line. It will never actually go higher than the line because if we have, for example, 100 enzymes, we only have 100 possible active sites. So even if we have, let's say, 200 substrate molecules because we have an excess of substrate molecules and only 100 active sites, we have a maximum activity at which only 100 active sites at a time can actually be filled. So as we increase our substrate concentration, we see that the enzyme activity increases up to a certain value known as the maximum enzyme activity or maximum enzyme velocity. So we see that at a constant concentration of enzyme, the enzyme activity will continue to rise until a certain maximum value is reached, known as the maximum velocity. And the maximum velocity represents the condition in which all the active sites this should be active, not activate.