Intrinsic pathway process

- The longer pathway and initiated by factor XII (a zymogen) into factor XIIa (an activated protease. Moreover, this is done upon the exposure to endothelial collagen. - Then factor XIIa will then activate factor XI to factor XIa. - Then factor XIa will then activate factor IX to factor IXa. - Then together with the factor IXa is the cofactor VIIIa which will activate factor X to factor Xa. - From there on, the common pathway begins.