Figure 1.
Simplified Coagulation Cascade. Clot formation as activated through the extrinsic pathway (red), the intrinsic pathway (blue) and the common pathway (green). Components of these pathways are measured by prothrombin time, activated partial thromboplastin time, and thrombin time are circled in red, blue, and yellow, respectively. Factors are indicated with a roman numeral and an “a” if activated. Abbreviations: Ca2+, calcium ions; FBGN, fibrinogen; HMWK, high-molecular-weight kininogen; PL, platelet membrane phospholipid; PK, prekallikrein; TF, tissue factor.