<prompt> Factor Xa is necessary for conversion of prothrombin to thrombinOnly in the extrinsic pathwayOnly in the intrinsic pathwayAs part of both extrinsic and intrinsic pathwaysOnly if the normal blood clotting cascade is inhibited  <response>: Ans. c As part of both extrinsic and intrinsic pathwaysRef: Robbins 9thpg 118-119; 8thpg 119Activated factor IX along with factor VIIIa Intrinsic pathway factor VIIa extrinsic pathway, converge to activate Factor X to Xa is necessary for conversion of prothrombin to thrombin common pathway 