Question

Which one has no role in blood coagulation?

• A. Vitamin D
• B. Fibrinogen
• C. Calcium
• D. Vitamin K

Answer 1

The correct option is A Vitamin D

Blood coagulation

The mechanism that the body employs to stop the flow of blood from an injury/ wound/ cut is called coagulation of blood or blood clotting.​

Prothrombin is formed by the liver. Vitamin K is required by the liver for the formation of prothrombin.

If the liver fails to produce prothrombin then the concentration of prothrombin falls in the plasma, which leads to failure in blood coagulation.

The prothrombin activator (thrombokinase), in the presence of calcium ions, causes conversion of prothrombin to thrombin.

Blood coagulation

Thrombin acts as an enzyme to convert fibrinogen into fibrin fibres that form a mesh called clot.

Calcium ions are required for the most steps of coagulation. Besides, they are also required for the acceleration of the clotting reactions. So, without enough calcium ions in blood, blood would not clot properly.

Vitamin D has no role to play in blood clotting.

Final answer
(D) Vitamin D