Deficiency of which of the following factors does not cause an abnormality of the intrinsic pathway
a. There are two pathways involved in coagulation blood.
b. The intrinsic pathway begins with factor XII and through a cascade of enzymatic reactions, activates factors XI, IX, and VII in sequence. This pathway is referred to as "intrinsic" because all of the components leading ultimately to fibrin clot formation are intrinsic to the circulating plasma and no surface is required to initiate the process.
c. The extrinsic pathway requires exposure of tissue factor on the surface of the injured vessel wall to initiate the arm of the cascade beginning with factor VII. The two arms of the coagulation cascade merge to a common pathway at factor X, and activation proceeds in sequence of factors II (prothrombin) and I (fibrinogen). Clot formation occurs after proteolytic conversion of fibrinogen to fibrin.