The component in blood responsible for clotting is called platelets, or thrombocytes. These small, disc-shaped cell fragments are produced in the bone marrow and play a vital role in hemostasis, the process that prevents excessive bleeding. When a blood vessel is injured, platelets adhere to the site, forming a temporary plug and releasing chemical signals that attract more platelets. This aggregation, along with the activation of clotting factors, leads to the formation of a stable fibrin clot, ensuring that blood loss is minimized during injuries.