Stylized curve of thrombin generation during hemostatic coagulation. The lag before the onset of measurable thrombin generation corresponds to the initiation and amplification phases. During this period, a small amount of thrombin is produced, which participates in feedback amplification of the procoagulant signal. The large burst of thrombin generation that takes place on platelet surfaces during the propagation phase is responsible for the peak of measurable thrombin activity. Both the rate of thrombin generation (#2) and the total amount of thrombin activity (#3) play important roles in determining clot structure and stability.