The extrinsic pathway is one of the two main pathways that lead to blood coagulation, or clotting. It is triggered by external factors, specifically when tissue damage occurs, exposing tissue factor (TF) to the bloodstream. This pathway is faster than the intrinsic pathway and primarily involves the activation of factor VII, which then activates factor X to initiate the clotting process. Once factor X is activated, it combines with factor V to form the prothrombinase complex. This complex converts prothrombin into thrombin, an essential enzyme that transforms fibrinogen into fibrin, creating a stable blood clot. The extrinsic pathway is crucial for rapid response to injury and helps prevent excessive bleeding.