And it's the fibrin that ultimately forms our blood clots, which basically looks something like this. And we'll see exactly what that is in just a moment. So we see that the blood clot cascade is actually a pretty complicated cascade. And actually it involves even more molecules than shown on the board. And what it also has is many different types of positive feedback loops. For instance, what Thrombin actually does is it not only activates fibrinogen into fibrin, as we'll discuss in detail in just a moment, thrombin also creates many different positive feedback loops.