does the active x factor catalyses the conversion of fibrinogen to fibrin or prothrombin to thrombin

The active X factor, also known as Factor Xa, catalyzes the conversion of prothrombin to thrombin.

Here’s a detailed explanation:

1. Role of Factor Xa: Factor Xa is an essential enzyme in the coagulation cascade, a series of events that lead to blood clotting. It is produced when Factor X is activated by either the intrinsic or extrinsic pathway of coagulation.

2. Conversion to Thrombin: Once activated, Factor Xa converts prothrombin (Factor II) into thrombin (Factor IIa). Thrombin plays a crucial role in the coagulation process, leading to the conversion of fibrinogen to fibrin, which ultimately forms a stable blood clot.

3. Fibrinogen to Fibrin: After prothrombin is converted to thrombin by the action of Factor Xa, thrombin then acts on fibrinogen. Thrombin cleaves fibrinogen into fibrin monomers, which aggregate to form a fibrin mesh, necessary for clot stabilization.

In summary, the active X factor (Factor Xa) specifically catalyzes the conversion of prothrombin to thrombin, which is a significant step in the blood coagulation process.