Primary Hemostasis

Primary hemostasis is the initial response of the body to stop bleeding when a blood vessel is injured. It involves the quick formation of a temporary "platelet plug." When a vessel is damaged, platelets (a type of blood cell) are activated and stick to the injury site, becoming sticky themselves. They aggregate, or clump together, forming a barrier that helps seal the wound. This process is crucial for preventing excessive blood loss, and sets the stage for further healing and the later phase of hemostasis, which involves reinforcing the plug with fibrin (a protein).