THE HUMAN IMMUNE SYSTEM
TYPES OF IMMUNITY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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I
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I
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III
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III
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Detailed explanation-1: -1) Constriction of the blood vessel. 2) Formation of a temporary “platelet plug.” 3) Activation of the coagulation cascade. 4) Formation of “fibrin plug” or the final clot.
Detailed explanation-2: -Blood coagulation occurs in the following sequence: Whenever there is rupture of blood vessels or damage is caused to blood, a complex of substances called prothrombin activator complex is formed. The activators convert prothrombin into thrombin. Thrombin acts as an enzyme and converts fibrinogen into fibrin threads.
Detailed explanation-3: -Proteins in the blood called clotting factors help specific blood cells stop bleeding. Thrombin is an enzyme in the liquid part of blood (plasma). It helps a clotting factor called fibrinogen turn into fibrin to create clots. Thrombin time is a measure of how long the blood’s plasma takes to form a clot.
Detailed explanation-4: -Thrombin therefore plays a role in coagulation (fibrin), platelet activation, regulation of coagulation activation (protein C), and controlling fibrinolysis (TAFI).