platelet plug

biology

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Last updated

July 1, 2026

Quick Summary

Platelets, also known as blood platelets or thrombocytes, are small, colorless blood components crucial for stopping bleeding. They are fragments of larger cells called megakaryocytes found in the bone marrow.12

When a blood vessel is injured, platelets aggregate at the site, forming a plug that helps seal the wound. They also provide a surface for fibrin to form a clot and release chemicals that constrict blood vessels, further aiding in clot formation. Platelets are essential for hemostasis, the process of preventing and controlling bleeding. Abnormalities in platelet number or function can lead to bleeding disorders.1345

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bleeding and blood clotting
Significance of hemostasis
…(2) the formation of a platelet plug, and (3) changes associated with the wall of the blood vessel after injury of its cells. In humans, defects in any of these processes may result in persistent bleeding from slight injuries, or, alternatively, in an overreaction that causes the inappropriate formation of…
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…(2) the formation of a platelet plug, and (3) changes associated with the wall of the blood vessel after injury of its cells. In humans, defects in any of these processes may result in persistent bleeding from slight injuries, or, alternatively, in an overreaction that causes the inappropriate formation of…
Read More