What converts soluble fibrinogen to insoluble fibrin?

Question

What converts soluble fibrinogen to insoluble fibrin?

Answer 1

Thrombin

Answer 2

Prothrombin activator causes the change of a plasma protein, prothrombin, to the active enzyme thrombin.  Thrombin.  Thrombin catalyzes (increases the rate of chemical reaction) the action of single fibrinogen molecules (another plasma protein made by the liver) to react together to form long, hairlike, insoluble fibrin strands.  They glue the platelets (clotting part of the blood) together and make a web that forms the basis for the clot.

Answer 3

Fibrin is made from its zymogen(inactive enzyme) fibrinogen, a soluble plasma glycoprotein that is synthesized by the liver. Processes in the coagulation cascade activate another zymogen, prothrombin, to the protease thrombin, which is responsible for converting fibrinogen into fibrin.

Essentially, a protein causes fibrinogen to become the active form, fibrin.