Factor which activates preaccelerin to Vila -: (A) Tissue factor, (B) Christmas factor, (C) Fibrim, (D) Prothrombin
Answer is A. Ans. is 'a' i.e., Tissue factor o Preaccelerin (factor VII) is activated to factor Vila by tissue factoro Tissue factor is the cofactor for both factor VII and Vilao When IF binds to factor VII it promotes its activation to Vilao When TF binds to Vila, the TF- Vila complex catalyzes the activation of factor X.