. Clots the blood,
Red blood cells
White blood cells
Plasma
Platelets

Platelets help the blood clotting process (or coagulation) by gathering at the site of an injury, sticking to the lining of the injured blood vessel, and forming a platform on which blood coagulation can occur. This results in the formation of a fibrin clot, which covers the wound and prevents blood from leaking out.

Explanation:

Blood is composed of plasma, red blood cells, white blood cells, and platelets. Blood platelets play a role in coagulation (the clotting of blood to stop bleed from an open wound); white blood cells play an important role in the immune system; red blood cells transport oxygen and carbon dioxide.

yeah that's all I can think of