Thrombus

Thrombus is another word for a blood clot. It forms when there is damage to the blood vessel. Platelets stick to the damaged vessel, attracted by the exposed collagen. The platelets form a platelet plug and stop the external bleeding. Chemicals released from the site attract clotting factors (see <a _fcknotitle="true" href="Clotting Cascade">Clotting Cascade</a>) which lead to fibrin formation. The fibrin sticks together and seals the wound forming the blood clot.

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