Blood Physiology Quiz PDF

Blood Physiology Quiz Part One: Simple MCQs 1. Which natural anticoagulant binds with thrombin to form a complex that activates protein C? a) Glycocalyx b) Antithrombin III c) Thrombomodulin d) Heparin 2. What percentage of thrombin is estimated to be adsorbed to fibrin threads, preventing...

Blood Physiology Quiz Part One: Simple MCQs 1. Which natural anticoagulant binds with thrombin to form a complex that activates protein C? a) Glycocalyx b) Antithrombin III c) Thrombomodulin d) Heparin 2. What percentage of thrombin is estimated to be adsorbed to fibrin threads, preventing excessive clot spread? a) 50-60% b) 70-80% c) 85-90% d) 95-100% 3. The primary source of heparin in the body is: a) Basophil cells b) Mast cells c) Endothelial cells d) Platelets 4. Heparin's anticoagulant action is significantly enhanced when it combines with: a) Protein C b) Antithrombin III c) Thrombomodulin d) Plasminogen 5. Which component of the fibrinolytic system is responsible for digesting fibrin threads and other protein coagulants? a) Plasminogen b) t-PA c) Plasmin d) Urokinase 6. The tissue plasminogen activator (t-PA) is primarily released from: a) Liver b) Injured tissues and vascular endothelium c) Platelets d) Red blood cells 7. Which of the following is NOT a plasminogen activator? a) Thrombin b) Urokinase c) Streptokinase d) Protein C 8. What is the primary function of the t-PA inhibitor? a) Activate plasminogen b) Delay fibrinolysis c) Enhance fibrinolysis d) Inhibit thrombin 9. Haemophilia A is caused by a deficiency in which clotting factor? a) Factor VIII b) Factor IX c) Factor XI d) Factor XII 10. Which condition is characterized by both excessive bleeding and intravascular clotting? a) Purpura b) Haemophilia c) Thrombo-embolic conditions d) Disseminated Intravascular Coagulation (DIC) Part Two: Complex MCQs 11. How does the smoothness of the endothelial surface contribute to the prevention of blood clotting? a) It enhances the activation of the intrinsic clotting system b) It promotes the adhesion of platelets to the vessel wall c) It prevents the contact activation of the intrinsic clotting system d) It increases the production of natural anticoagulants 12. The glycocalyx layer on the endothelium aids in preventing blood clot formation by: a) Activating clotting factors b) Repelling clotting factors and platelets c) Binding with thrombin d) Stimulating the production of protein C 13. If the endothelial wall is damaged, what is the potential consequence in terms of blood clotting? a) Increased production of natural anticoagulants b) Prevention of platelet activation c) Inhibition of the intrinsic clotting mechanism d) Activation of both factor XII and blood platelets, initiating the intrinsic clotting mechanism 14. What is the role of antithrombin III in regulating blood clotting? a) It directly activates the fibrinolytic system b) It adsorbs to fibrin threads, preventing clot spread c) It inactivates the remaining thrombin not adsorbed to fibrin d) It enhances the production of heparin 15. The effectiveness of antithrombin III in removing thrombin increases significantly when it combines with: a) Protein C b) Heparin c) Thrombomodulin d) Plasminogen 16. Apart from removing thrombin, the heparin-antithrombin complex also removes other activated coagulation factors, including: a) Factors V, VIII, and X b) Factors XII, XI, IX, and X c) Factors II, VII, and IX d) Factors I, III, and XIII 17. What triggers the conversion of plasminogen to plasmin in the fibrinolytic system? a) Presence of fibrin threads b) Release of t-PA from injured tissues c) Activation of factor XII d) Binding of thrombin to antithrombin III 18. The primary role of urokinase in the plasmin system is to: a) Prevent clot formation in the urinary tract b) Dissolve clots in blood vessels c) Delay fibrinolysis d) Activate factor XII 19. Which medical condition can benefit from the clinical use of fibrinolysis through the administration of t-PA, streptokinase, or urokinase? a) Haemophilia b) Purpura c) Acute myocardial infarction d) Vitamin K deficiency 20. In thrombocytopenic purpura, the platelet count typically falls below: a) 10,000/mm3 b) 30,000/mm3 c) 50,000/mm3 d) 70,000/mm3 21. Non-thrombocytopenic purpura can be caused by: a) Decreased platelet count b) Increased platelet count c) Decreased functioning platelets or defects in the vessel wall d) Excessive production of clotting factors 22. Which type of haemophilia is the most common, representing 85% of cases? a) Haemophilia A b) Haemophilia B c) Haemophilia C d) All types are equally common 23. Haemophilia is a: a) Sex-linked dominant disease b) Sex-linked recessive disease c) Autosomal dominant disease d) Autosomal recessive disease 24. Which of the following factors can contribute to thrombo-embolic conditions? a) Rapid blood flow b) Smooth vascular endothelium c) Very slow blood flow and roughness of vascular endothelium d) Increased production of natural anticoagulants 25. Disseminated Intravascular Coagulation (DIC) can be triggered by: a) Excessive vitamin K intake b) Retention of a dead foetus in the uterus, repeated blood transfusions, or septicemic shock c) Increased platelet count d) Decreased production of thromboplastin Answer Guide 1. c 2. c 3. b 4. b 5. c 6. b 7. d 8. b 9. a 10. d 11. c 12. b 13. d 14. c 15. b 16. b 17. b 18. a 19. c 20. c 21. c 22. a 23. b 24. c 25. b Done