Final answer:
In the process of hemostasis, platelets play a key role in sealing a ruptured blood vessel by forming a platelet plug. This plug is supported by a glycoprotein called von Willebrand factor and is formed through the clumping and binding of platelets to underlying collagen in the vessel.
Step-by-step explanation:
In the process of hemostasis, platelets play a key role in sealing a ruptured blood vessel. There are three steps to hemostasis: vascular spasm, the formation of a platelet plug, and coagulation. The platelet plug is formed when platelets clump together, become sticky, and bind to exposed collagen in the vessel.
The platelet plug is supported by a glycoprotein called von Willebrand factor. Platelets also release chemicals that contribute to hemostasis. If any step of hemostasis fails, excessive bleeding or hemorrhage can occur.