What activates the clotting process in blood?

The clotting process in blood, also known as coagulation, is primarily activated by platelets. When a blood vessel is injured, platelets adhere to the site of the injury and each other, forming a temporary "plug." They release chemical signals that further promote clotting and enhance the recruitment of additional platelets to the area. This cascade of events ultimately leads to the transformation of fibrinogen, a soluble plasma protein, into fibrin, which forms a stable mesh that solidifies the initial platelet plug and prevents further bleeding.

Red blood cells are primarily responsible for carrying oxygen throughout the body and do not play a direct role in the clotting process. White blood cells serve as key components of the immune system to defend against infection and do not actively contribute to blood coagulation. Plasma, the liquid component of blood, contains the clotting factors necessary for the coagulation process but does not initiate the clotting itself. Therefore, platelets are the actual agents that initiate and regulate the clotting process.