Haemostasis MCQs PDF

1. What is the primary function of hemostasis in the body? (A) Promoting blood flow (B) Preventing blood loss (C) Increasing blood viscosity (D) Enhancing blood clotting 2. Which stage of hemostasis involves the reinforcement of the platelet plug by a protein mesh? (A) Tertiary hemo...

1. What is the primary function of hemostasis in the body? (A) Promoting blood flow (B) Preventing blood loss (C) Increasing blood viscosity (D) Enhancing blood clotting 2. Which stage of hemostasis involves the reinforcement of the platelet plug by a protein mesh? (A) Tertiary hemostasis (B) Secondary hemostasis (C) Primary hemostasis (D) Quaternary hemostasis 3. What is fibrin used for in the process of clot formation? (A) To create a more stable clot (B) To dissolve clots (C) To prevent clotting (D) To initiate clot formation 4. What is the term to describe the clumping up of platelets in primary hemostasis? (A) Adhesion (B) Activation (C) Aggregation (D) Exposure 5. What is another term for clot retraction? (A) Clot stabilization (B) Clot dissolution (C) Clot expansion (D) Clot formation 6. In primary hemostasis, what is the first step that occurs after endothelial injury? (A) Activation (B) Adhesion (C) Exposure (D) Aggregation 7. What is the main purpose of secondary hemostasis? (A) Reinforcing the platelet plug (B) Initiating platelet aggregation (C) Promoting endothelial repair (D) Activating clot retraction 8. What can students achieve by the end of the session regarding primary haemostasis? (A) Ability to describe primary haemostasis (B) Knowledge of clotting factors (C) Understanding of secondary haemostasis (D) Understanding of blood cell formation 9. Which component makes up the mortar between the 'bricks' of platelets in primary hemostasis? (A) Fibrin (B) Thrombin (C) Collagen (D) Heparin 10. Which of the following is NOT a reference source mentioned in the content? (A) Medical Physiology (B) Physiology (C) Human Anatomy & Physiology (D) Chemistry Principles 11. What is the significance of primary hemostasis in the overall process of hemostasis? (A) It promotes fibrinolysis (B) It activates the coagulation cascade (C) It forms the initial platelet plug (D) It triggers clot retraction 12. What is the purpose of primary platelet adhesion receptors according to the content? (A) To initiate clot formation (B) To promote platelet adhesion (C) To prevent platelet aggregation (D) To dissolve clots 13. During hemostasis, what is the role of fibrin in the formation of a stable clot? (A) Inhibiting coagulation factors (B) Creating a protein mesh (C) Activating platelets (D) Dissolving the clot 14. Which term describes the process of platelets sticking to the exposed collagen at the site of injury in hemostasis? (A) Activation (B) Adhesion (C) Aggregation (D) Exposure 15. What are the factors, enzymes, and hormones secreted by endothelial injuries in primary haemostasis? (A) Von Willebrand factor, tissue factor, prostacyclin, nitric oxide (B) Vitamin C, collagen, insulin, serotonin (C) Fibrinogen, heparin, adrenaline, histamine (D) Plasminogen, thrombin, erythropoietin, dopamine 16. What would be the consequence of impaired hemostasis in the body? (A) Increased risk of uncontrolled bleeding (B) Enhanced wound healing (C) Reduced blood viscosity (D) Accelerated blood flow 17. Why does platelet activation stop during and how does the primary haemostasis stop? (A) Platelet aggregation; stops due to clot retraction (B) Due to lack of calcium ions; stops due to negative feedback loop activation (C) Platelet exhaustion; stops due to fibrinolysis inhibition (D) Platelet degranulation; stops due to prostaglandin release 18. What is the function of the elastic fibers in the blood vessel? (A) To control the size of the lumen, or the inner diameter of the vessel by contraction and relaxation (B) To give the blood vessel the ability to expand and contract. (C) To protect the vessel and anchor it to the surrounding tissues (D) To trigger a reflexive contraction of the smooth muscles near the injury site 19. What is the primary function of Von Willebrand factor in the process of haemostasis? (A) Inhibits fibrin formation (B) Promotes platelet adhesion to damaged endothelium (C) Activates the intrinsic pathway of coagulation (D) Degrades fibrin clots 20. What is the primary of endothelial cells in blood vessels? (A) To control the size of the lumen (B) To detect injuries and trigger vascular spasms (C) To secrete nitric oxide and prostaglandins (D) To anchor the vessel to surrounding tissues 21. Which of the following is NOT a component of the coagulation cascade? (A) Factor VIII (B) Factor X (C) Protein C (D) Thromboxane A2 22. What is the role of smooth muscle cells in blood vessels during injury? (A) To trigger a reflexive contraction near the injury site (B) To expand the vessel for increased blood flow (C) To secrete collagen for structural support (D) To detect the injury and initiate a vascular spasm 23. What is the role of thromboxane A2 in platelet aggregation? (A) Inhibits platelet activation (B) Stimulates platelet aggregation (C) Promotes vasoconstriction (D) Prevents clot formation 24. How do nitric oxide and prostaglandins affect smooth muscles in blood vessels? (A) Induce a reflexive contraction near the injury site (B) Stimulate the production of elastic fibers (C) Cause relaxation of nearby smooth muscles (D) Promote the secretion of collagen 25. Which enzyme is responsible for converting fibrinogen to fibrin in the coagulation cascade? (A) Plasmin (B) Factor XII (C) Thrombin (D) Protein S 26. What is the purpose of a vascular spasm in response to an arterial injury? (A) To narrow the vessel and reduce blood flow (B) To widen the vessel for better circulation (C) To anchor the vessel to surrounding tissues (D) To trigger a release of clotting factors 27. What is the primary function of antithrombin III in the coagulation process? (A) Promotes platelet aggregation (B) Activates factor V (C) Inhibits thrombin activity (D) Enhances fibrinolysis 28. Which component of the blood vessel is responsible for the structural integrity and protection of the vessel? (A) Collagen in the connective tissue (B) Smooth muscle cells (C) Elastic fibers (D) Endothelial cells 29. Which vitamin is essential for the synthesis of clotting factors II, VII, IX, and X? (A) Vitamin K (B) Vitamin D (C) Vitamin E (D) Vitamin B12 30. What happens when the smooth muscle cells contract in a blood vessel? (A) The lumen size decreases (B) The vessel expands for increased blood flow (C) The endothelium secretes nitric oxide (D) The vessel becomes more rigid 31. What is the main function of plasmin in the fibrinolytic system? (A) Degrades fibrin clots (B) Promotes platelet activation (C) Inhibits thrombin formation (D) Activates factor VIII 32. Why is it important for blood vessels to have the ability to expand and contract? (A) To trigger a vascular spasm (B) To anchor the vessel to surrounding tissues (C) To regulate blood flow and pressure (D) To detect injuries and initiate repair processes 33. Which of the following is a natural anticoagulant produced by the body? (A) Warfarin (B) Heparin (C) Aspirin (D) Clopidogrel 34. What is the function of collagen in the blood vessel structure? (A) To regulate the size of the lumen (B) To provide structural support and protection (C) To trigger smooth muscle contractions (D) To facilitate the secretion of nitric oxide 35. What happens when there's endothelial? (A) Secretion ofric oxide and prostaglandins increases (B) Endothelial cells multiply rapidly (C) Secretion of nitric oxide and prostaglandins decreases (D) Endothelial cells become transparent 36. What protein do endothelial cells secrete when there's injury? (A) Prostaglandins (B) Nitric oxide (C) Endothelin (D) Collagen 37. What is the protein released by damaged endothelial cells that binds to exposed collagen? (A) Von Willebrand's factor (B) GP1B protein (C) Endothelin (D) Serotonin 38. What is the first step after exposure of collagen due to endothelial cell damage? (A) Adhesion of platelets (B) Activation of platelets (C) Secretion of nitric oxide (D) Multiplication of endothelial cells 39. Which surface protein on platelets allows them to bind to Von Willebrand factor? (A) Thromboxane A2 receptor (B) GP1B protein (C) Nitric oxide receptor (D) Von Willebrand factor receptor 40. What happens when platelets bind to Von Willebrand factor via GP1B? (A) Platelets shrink in size (B) Platelets release nitric oxide (C) Platelets get activated (D) Platelets become transparent 41. What do platelets release more of when activated? (A) Von Willebrand factor (B) Serotonin (C) Calcium (D) Nitric oxide 42. Which molecules are secreted by platelets to activate other platelets? (A) Calcium and Von Willebrand factor (B) ADP and thromboxane A2 (C) Nitric oxide and serotonin (D) Prostaglandins and endothelin 43. What is the role of calcium released by platelets during activation? (A) Activate secondary hemostasis (B) Attract more platelets to the area (C) Form tentacle-like arms (D) Induce endothelial cell proliferation 44. What is the function of ADP and thromboxane A2 released by platelets? (A) Inhibit platelet aggregation (B) Promote endothelial cell growth (C) Activate other platelets (D) Prevent smooth muscle contraction 45. What is the main function of prostlandin and nit oxide in the platelet process? (A) Inhibit platelets (B) Destroy platelets (C) Activate plate (D) Transform platelets 46. What is the role ADP and thromboxane A2 in platelet activation? (A) Inhibit platelets (B) Activate platelets (C) Destroy platelets (D) Transform platelets 47. What happens when platelets express GPIIB/IIIA? (A) They become dormant (B) They disintegrate (C) They are considered fully activated (D) They change shape 48. Which blood protein acts like handcuffs linking platelets together during hemostasis? (A) Nitric oxide (B) Prostaglandin (C) Fibrinogen (D) Thromboxane A2 49. What is the final step in the process of platelet activation? (A) Activation (B) Adhesion (C) Aggregation (D) Exposure 50. What is the purpose of GPIIB/IIIA receptors on platelets? (A) To inhibit platelet activation (B) To bind to collagen (C) To destroy platelets (D) To link platelets together 51. Which molecules are considered platelet inhibitors in the tug-of-war described in the text? (A) ADP and thromboxane A2 (B) Fibrinogen and collagen (C) Prostaglandin and nitric oxide (D) GPIIB/IIIA and endothelial cells 52. What limits the positive feedback loop of platelet activation to the injury site? (A) Prostaglandin and nitric oxide (B) Fibrinogen and collagen (C) ADP and thromboxane A2 (D) GPIIB/IIIA and endothelial cells 53. What is the primary function of fibrinogen in the platelet activation process? (A) Activate platelets (B) Link platelets together (C) Inhibit platelets (D) Destroy platelets 54. What is the primary function of platelet plug formation in hemostasis? (A) To prevent further blood loss from a damaged vessel (B) To secrete nitric oxide and prostaglandins (C) To expand and contract the lumen of blood vessels (D) To protect the vessel with collagen fibers 55. What occurs during secondary hemostasis? (A) Platelets aggregate at the site of injury to form a plug (B) Smooth muscle cells anchor the vessel to surrounding tissues (C) Fibrinogen is cleaved into fibrin to form a protein mesh (D) Collagen fibers reinforce the platelet plug 56. In the context of hemostasis, what is the purpose of a protein mesh made of fibrin? (A) To reinforce the platelet plug (B) To expand and contract the blood vessel lumen (C) To secrete nitric oxide and prostaglandins (D) To protect the vessel with collagen fibers 57. What is the role of collagen fibers in the process of hemostasis? (A) To secrete nitric oxide and prostaglandins (B) To protect the vessel and anchor it to surrounding tissues (C) To form a protein mesh around the platelet plug (D) To expand and contract the lumen of blood vessels 58. Why is secondary hemostasis necessary after primary hemostasis? (A) To secrete nitric oxide and prostaglandins (B) To expand and contract the blood vessel lumen (C) To further reinforce the platelet plug (D) To protect the vessel with collagen fibers