Bleeding and Thrombosis ( Hematology MCQ’s ) PDF Download
61 In the human hemostatic system, procoagulant forces include ?
A. Platelet adhesion
B. Platelet aggregation
C. Fibrin clot formation
D. All of the above
Explanation:- In the human hemostatic system, procoagulant forces include platelet adhesion and aggregation and fibrin clot formation.
62 The major components of the hemostatic system are ?
A. Platelets, monocytes and red cells
B. Plasma proteins
C. Vessel wall
D. All of the above
Explanation:- Major components of the hemostatic system platelets & other formed elements of blood (monocytes & RBCs), plasma proteins (coagulation & fibrinolytic factors & inhibitors) and vessel wall.
63 Formed element of blood that is not a component of the hemostatic system is ?
A. Neutrophil
B. Monocyte
C. Red cell
D. Platelet
Explanation:- Major components of hemostatic system are platelets, monocytes & red cells, plasma proteins (coagulation & fibrinolytic factors & inhibitors) and vessel wall itself.
64 Platelet adhesion is mediated primarily by ?
A. von Willebrand factor (vWF)
B. Gp IIb/IIIa
C. Gp Ia/IIa
D. Fibronectin
Explanation:- Platelet adhesion is mediated primarily by von Willebrand factor (vWF).
65 Which of the following is false about von Willebrand factor (VWF) ?
A. Large multimeric protein
B. Present in plasma
C. Present in extracellular matrix of subendothelial vessel wall
D. None of the above
Explanation:- von Willebrand factor (VWF) is a large multimeric protein present in both plasma & extracellular matrix of subendothelial vessel wall. It serves as the primary “molecular glue” to withstand high levels of shear stress that would detach platelets due to flow of blood.
66 Which of the following is released from activated platelets ?
A. Epinephrine
B. Thrombin
C. Adenosine diphosphate
D. All of the above
Explanation:- Platelet adhesion is followed by platelet activation and aggregation which is enhanced & amplified by humoral mediators in plasma (epinephrine, thrombin), mediators released from activated platelets (adenosine diphosphate, serotonin) & vessel wall extracellular matrix constituents that come in contact with adherent platelets (collagen, VWF).
67 Most abundant receptor on the platelet surface is ?
A. Gp Ia/IIa
B. Gp Ib/IX
C. Gp IIb/IIIa
D. Gp VI
Explanation:- Platelet glycoprotein (Gp) IIb/IIIa (IIb3) complex is the most abundant receptor on platelet surface.
68 Platelet surface receptor GpIIB / IIIa binds to ?
A. Thrombospondin
B. Fibrinogen
C. Collagen
D. All of the above
Explanation:- Platelet activation converts the normally inactive GpIIb/IIIa receptor into an active receptor enabling its binding to fibrinogen and vWF.
69 Surface of each platelet has how many GpIIb / IIIa binding sites ?
A. ~ 10,000
B. ~ 25,000
C. ~ 50,000
D. ~ 100,000
Explanation:- Surface of each platelet has ~50,000 GpIIb/IIIa binding sites.
70 Tissue factor (TF) is present on ?
A. Subendothelial cellular components of vessel wall
B. Circulating microparticles from monocytes
C. Circulating microparticles from platelets
D. All of the above
Explanation:- TF is expressed on surfaces of subendothelial cellular components of vessel wall (smooth-muscle cells & fibroblasts). TF is present in circulating microparticles shed from monocytes & platelets.
71 Which of the following is a serine protease factor ?
A. III
B. VIIa
C. IX
D. X
Explanation:- TF binds serine protease factor VIIa and their complex (TF+VIIa) activates factor X to factor Xa. Factor IXa also activates factor X to factor Xa.
72 Essential cofactor for conversion of prothrombin to thrombin is ?
A. Va
B. VIIa
C. IX
D. X
Explanation:- Factor Xa converts prothrombin to thrombin, the pivotal protease of the coagulation system. The essential cofactor for this reaction is factor Va. Factor Va is produced by thrombin-induced limited proteolysis of factor V.
73 Which of the following in endothelial cells has antithrombotic effect ?
A. Prostacyclin
B. Nitric oxide
C. EctoADPase/CD39
D. All of the above
Explanation:- Prostacyclin, nitric oxide & ectoADPase/CD39 produced from endothelial cells act to inhibit platelet binding, secretion and aggregation.
74 Anticoagulant factor produced by endothelial cells is ?
A. Heparan proteoglycans
B. Antithrombin
C. Thrombomodulin
D. All of the above
Explanation:- Endothelial cells produce anticoagulant factors like heparan proteoglycans, antithrombin, TF pathway inhibitor and thrombomodulin.
75 Which of the following produced by endothelial cells acts as an anticoagulant ?
A. Plasminogen activator inhibitor
B. Thrombomodulin
C. Prostacyclin
D. Nitric oxide
76 Endothelial cells activate fibrinolytic mechanisms through the production of ?
A. Tissue plasminogen activator 1
B. Urokinase
C. Plasminogen activator inhibitor
D. All of the above
Explanation:- Endothelial cells activate fibrinolytic mechanisms through the production of tissue plasminogen activator 1, urokinase, plasminogen activator inhibitor & annexin-2.
77 Which of the following best relates to heparin ?
A. Antithrombin III
B. Protein C
C. Protein S
D. All of the above
Explanation:- Antithrombin III inhibits thrombin by forming inactivating complexes that increase several folds in the presence of heparin.
78 Which of the following becomes an anticoagulant when it is activated by thrombin ?
A. Antithrombin III
B. Protein C
C. Protein S
D. Tissue factor pathway inhibitor (TFPI)
Explanation:- Protein C is a plasma glycoprotein that becomes an anticoagulant when activated by thrombin.
79 Which of the following about thrombomodulin is false ?
A. Transmembrane proteoglycan binding site for thrombin on endothelial cell surface
B. Thrombin-induced activation of protein C occurs physiologically on thrombomodulin
C. Anticoagulant factor from endothelial cell
D. None of the above
Explanation:- Thrombomodulin expressed on the surface of endothelial cells binds thrombin at low concentrations and inhibits coagulation through activation of the protein C pathway, leading to enhanced catabolism of clotting factors Va and VIIIa, thereby combating thrombus formation.
80 Activated protein C acts as an anticoagulant by cleaving and inactivating activated factor ?
A. II
B. V
C. VI
D. X
Explanation:- Activated protein C acts as an anticoagulant by cleaving & inactivating activated factors V & VIII.
81 Which of the following relates to protein S ?
A. Cofactor
B. Glycoprotein
C. Vitamin K dependent posttranslational modification
D. All of the above
Explanation:- Glycoprotein Protein S is a cofactor that undergoes vitamin K dependent posttranslational modification. It accelerates the reaction of activated protein C with factors V and VIII.
82 Which of the following inhibits TF / FVIIa / FXa complex ?
A. Activated protein C
B. Protein S
C. Tissue factor pathway inhibitor (TFPI)
D. All of the above
Explanation:- Tissue factor pathway inhibitor (TFPI) is a plasma protease inhibitor that regulates the TF– induced extrinsic pathway of coagulation. TFPI inhibits the TF/FVIIa/FXa complex.
83 Tissue factor pathway inhibitor (TFPI) be released by ?
A. Heparin
B. Streptokinase
C. Urokinase
D. All of the above
Explanation:- TFPI is bound to lipoprotein and can also be released by heparin from endothelial cells, where it is bound to glycosoaminoglycans, and from platelets.
84 Plasminogen activators (tPA & uPA) cleave which bond of plasminogen to generate the active enzyme plasmin ?
A. Arg460 – Val461
B. Arg560 – Val561
C. Arg660 – Val661
D. Arg760 – Val761
Explanation:- Plasminogen activators (tissue type plasminogen activator & urokinase type plasminogen activator cleave Arg560-Val561 bond of plasminogen to generate the active enzyme plasmin which is the major protease enzyme of the fibrinolytic system, acting to digest fibrin to fibrin degradation products.
85 “Fibrin specific” activity of plasmin is due to its ?
A. Arginine-binding sites
B. Lysine-binding sites
C. Valine-binding sites
D. Leucine-binding sites
Explanation:- The lysine-binding sites of plasmin (and plasminogen) permit it to bind specifically to fibrin and therefore physiologic fibrinolysis is “fibrin specific”.
86 Physiologic regulation of fibrinolysis is done by ?
A. Plasminogen activator inhibitors (PAI-1 & PAI-2)
B. Thrombin-activatable fibrinolysis inhibitor (TAFI)
C. 2-antiplasmin
D. All of the above
87 Which of the following antiplasmin inhibits plasmin ?
A. 1 antiplasmin
B. 2 antiplasmin
C. 3 antiplasmin
D. 4 antiplasmin
Explanation:- PAI1 is the primary inhibitor of tPA & uPA and 2 antiplasmin is the main inhibitor of plasmin in human plasma, inactivating any nonfibrin clot associated plasmin.
88 Epistaxis is the most common symptom in ?
A. Hemophilia A
B. Ehlers-Danlos syndrome
C. Hereditary hemorrhagic telangiectasia
D. Cushing’s syndrome
Explanation:- Epistaxis is the most common symptom in hereditary hemorrhagic telangiectasia & in boys with VWD.
89 Menorrhagia is a common symptom in women with ?
A. VWD
B. Factor XI deficiency
C. Symptomatic carriers of hemophilia A
D. All of the above
Explanation:- Menorrhagia is a common symptom in women with underlying bleeding disorders. It is seen in majority of women with VWD & factor XI deficiency & in symptomatic carriers of hemophilia A.
90 Which of the following is called a “life-threatening site of bleeding” ?
A. Bleeding into oropharynx
B. Bleeding into central nervous system
C. Bleeding into retroperitoneum
D. All of the above
Explanation:- Life-threatening sites of bleeding include bleeding into oropharynx, into central nervous system, and into retroperitoneum.
91 Which of the following about clopidogrel is false ?
A. Thienopyridine
B. Inhibits ADP-mediated platelet aggregation
C. Can precipitate or exacerbate bleeding symptoms
D. None of the above
Explanation:- Thienopyridines (clopidogrel and prasugrel) inhibit ADP-mediated platelet aggregation and like NSAIDs can precipitate or exacerbate bleeding symptoms.
92 Herb with potential anti-platelet activity is ?
A. Ginger
B. Turmeric
C. Garlic
D. All of the above
Explanation:- Herbs with potential anti-platelet activity include Ginkgo, Garlic, Bilberry, Ginger, Dong quai, Feverfew, Asian, Siberian & American ginseng, Turmeric, Meadowsweet and Willow.
93 Which of the following is a Coumarin containing herb ?
A. Motherworth
B. Chamomile
C. Horse chestnut
D. All of the above
Explanation:- Coumarin containing herbs include Motherworth (Leonurus cardiaca), Chamomile (Matricaria recutita, Chamaemelum mobile), Horse chestnut (Aesculus hippocastanum) Red clover (Trifolium pratense) Fenugreek (Trigonella foenum-graecum).
94 Bruising or mucosal bleeding may be the presenting complaint in ?
A. Liver disease
B. Severe renal impairment,
C. Hypothyroidism
D. All of the above
Explanation:- Bruising or mucosal bleeding may be the presenting complaint in liver disease, severe renal impairment, hypothyroidism, paraproteinemias or amyloidosis & bone marrow failure.
95 All coagulation factors are synthesized in ?
A. Liver
B. Kidney
C. Lungs
D. None of the above
Explanation:- All coagulation factors are synthesized in liver & hepatic failure results in combined factor deficiencies.
96 Which of the following coagulation factors is dependent on vitamin K for posttranslational modification ?
A. Factor II
B. Factor VII
C. Factor IX
D. All of the above
97 Which of the following proteins is dependent on vitamin K for posttranslational modification ?
A. Protein C
B. Protein S
C. Protein Z
D. All of the above
Explanation:- Coagulation factors II, VII, IX, X and proteins C, S, and Z are dependent on vitamin K for posttranslational modification.
98 Normal blood platelet count is ?
A. 50,000 to 100,000/μL
B. 100,000 to 250,000/μL
C. 150,000 to 450,000/μL
D. 250,000 to 550,000/μL
Explanation:- Normal blood platelet count is 150,000 to 450,000/μL.
99 Thrombocytopenia results from ?
A. Decreased production of platelets
B. Increased destruction of platelets
C. Sequestration of platelets
D. Any of the above
Explanation:- Thrombocytopenia results from decreased production, increased destruction, &/or sequestration.
100 Bleeding rarely occurs in isolated thrombocytopenia at counts ?
A. < 50000 / μL
B. < 80000 / μL
C. < 100000 / μL
D. < 150000 / μL
Explanation:- Bleeding rarely occurs in isolated thrombocytopenia at counts < 50000 / μL.
101 Most procedures can be performed in patients with a platelet count of ?
A. < 50000 / μL
B. < 80000 / μL
C. < 100000 / μL
D. < 150000 / μL
Explanation:- Most procedures can be performed in patients with a platelet count of 50,000/μL. For major surgery, a count of about 80,000/μL is likely to be sufficient.
102 The major risk factor for arterial thrombosis is ?
A. Atherosclerosis
B. Hyperhomocysteinemia
C. Dysfibrinogenemia
D. Hormonal therapy
Explanation:- The major risk factor for arterial thrombosis is atherosclerosis. Risk factors for venous thrombosis are immobility, surgery, underlying medical conditions, malignancy, hormonal therapy, obesity, and genetic predispositions.
103 Most coagulation assays are performed in plasma anticoagulated with ?
A. Ethylenediamine tetraacetic acid (EDTA)
B. Sodium citrate
C. Heparin
D. Any of the above
Explanation:- Most coagulation assays are performed in sodium citrate anticoagulated plasma that is recalcified for the assay.
104 PT assesses the factors except ?
A. Factor I
B. Factor II
C. Factor V
D. Factor VIII
Explanation:- PT assesses factors I (fibrinogen), II (prothrombin), V, VII, and X. PT only measures one aspect of hemostasis affected by liver dysfunction.
105 International normalized ratio (INR) is calculated by ?
A. PT ratio x International Sensitivity Index (ISI)
B. PT ratio ÷ International Sensitivity Index (ISI)
C. PT ratio + International Sensitivity Index (ISI)
D. (PT ratio)International Sensitivity Index (ISI)
Explanation:- International normalized ratio (INR) is calculated by the formula: INR = (PTpatient/PTnormal mean)ISI.
106 Activated partial thromboplastin time (aPTT) assesses which of the following factors ?
A. Factor VIII
B. Factor IX
C. Factor X
D. All of the above
Explanation:- aPTT assesses the intrinsic & common coagulation pathways, factors XI, IX, VIII, X, V, II, fibrinogen, and also prekallikrein, high-molecular-weight kininogen & factor XII.
107 Structure of Fibrinogen is ?
A. Uninodular
B. Binodular
C. Trinodular
D. Quadrinodular
Explanation:- Fibrinogen is a trinodular structure consisting of 2 D domains and 1 E domain.
108 Cross-linking of the D domains on adjacent fibrinogen molecules is done by ?
A. FX
B. FXI
C. FXII
D. FXIIIa
Explanation:- Cross-linking of D domains on adjacent fibrinogen molecules is done by FXIIIa.
109 Which of the following about D-Dimers is false ?
A. Product of complete lysis of fibrin
B. Released when plasmin acts on fibrin
C. Relatively specific test of fibrin degradation
D. Relatively specific test of fibrinogen degradation
Explanation:- D-Dimers are the product of complete lysis of fibrin, maintaining the cross-linked D domains. When plasmin acts on covalently cross-linked fibrin, D-dimers are released. D-dimers in plasma are as a relatively specific test of fibrin rather than fibrinogen degradation. D-Dimer assays are a sensitive marker of blood clot formation and coagulation activation.
110 Normal level of D-Dimer in blood is ?
A. < 500 pg/mL
B. < 500 ng/mL
C. < 500 μg/mL
D. < 500 mg/mL
Explanation:- Normal level of D-Dimer in blood is < 500 ng/mL.
111 Plasma level of D-Dimer is ?
A. 0.22 – 0.74 mg/mL
B. 0.22 – 0.74 μg/mL
C. 0.22 – 0.74 ng/mL
D. 0.22 – 0.74 pg/mL
Explanation:- Plasma level of D-Dimer is 0.22 – 0.74 μg/mL.
112 D-dimer levels increase in patients with ?
A. Myocardial infarction
B. Pneumonia
C. II or III trimester of pregnancy
D. All of the above
Explanation:- D-dimer levels increase in myocardial infarction, pneumonia, intestinal ischemia, sepsis, cancer, postoperative state, initial infusion of human or humanized antibodies (rituximab, gemtuzumab, trastuzumab), and second or third trimester of pregnancy. D-dimer elevation is not as predictive of DVT in cancer patients as it is in patients without cancer.
113 Platelet interaction with vascular collagen is stabilized by ?
A. Gp Ia/IIa
B. Gp VI
C. von Willebrand factor (vWF)
D. FcRg
Explanation:- von Willebrand factor (vWF) is an adhesive glycoprotein that allows platelets to remain attached to the vessel wall despite the high shear forces generated within the vascular lumen by stabilizing interaction between platelets with collagen.
114 Platelet surface receptor GpIb / IX binds to ?
A. vWF
B. Fibrinogen
C. Collagen
D. All of the above
115 vWF forms a link between collagen fibrils & which of the following platelet receptor ?
A. Gp Ia/IIa
B. Gp Ib/IX
C. Gp VI
D. All of the above
Explanation:- GpIb/IX complex binds vWF. Adhesion of platelets with vessel wall is stabilized by von Willebrand factor, which forms a bridge between collagen fibrils in the vessel wall & receptors on platelet glycoprotein Ib/IX. Similarly, platelet aggregation is mediated by fibrinogen, which links adjacent platelets via receptors on the platelet glycoprotein IIb/IIIa complex.
116 Formation of thromboxane A2 (TXA2) from arachidonic acid is mediated by enzyme ?
A. Phospholipase C
B. Phospholipase A2
C. Cyclooxygenase
D. All of the above
Explanation:- Formation of TXA2 from arachidonic acid is mediated by the enzyme cyclooxygenase.
117 Platelet surface receptor GpIa/IIa binds to ?
A. vWF
B. Fibrinogen
C. Collagen
D. All of the above
Explanation:- GpIa/IIa binds collagen.
118 Platelet surface receptor GpVI / FcRIIa binds to ?
A. vWF
B. Fibrinogen
C. Collagen
D. All of the above
Explanation:- GpVI/Fc RIIa binds collagen.
119 After leaving bone marrow, what proportion of platelets are sequestered in spleen ?
A. One-third
B. One-half
C. Two-thirds
D. Three-fourths
120 The life span of platelets in circulation is about ?
A. 1 to 3 days
B. 3 to 5 days
C. 5 to 7 days
D. 7 to 10 days
Explanation:- After leaving bone marrow, ~one-third of platelets are sequestered in spleen, while the other two-thirds circulate for 7 to 10 days.
121 During menstrual cycle, platelet count rise at what time ?
A. Following ovulation
B. At the onset of menses
C. After completion of menstrual flow
D. Before ovulation
122 During menstrual cycle, platelet count fall at what time ?
A. Following ovulation
B. At the onset of menses
C. After completion of menstrual flow
D. Before ovulation
Explanation:- Platelet count varies in menstrual cycle, rising following ovulation & falling at onset of menses.
123 Platelet counts are decreased in which of the following deficiencies ?
A. Severe Iron deficiency
B. Folic acid deficiency
C. Vitamin B12 deficiency
D. All of the above
Explanation:- Platelet count are decreased in severe iron, folic acid or vitamin B12 deficiency.
124 Secondary or reactive thrombocytosis is due to which property of platelets ?
A. Hormonal
B. Acute-phase reactant
C. Enzymatic
D. All of the above
Explanation:- Platelets are acute-phase reactants. Secondary or reactive thrombocytosis refers to an increase in platelet counts in patients with systemic inflammation, tumors, bleeding & mild iron deficiency.
125 Which of the following cytokines interleukins stimulate platelet production in acute inflammation ?
A. IL-3
B. IL-6
C. IL-11
D. All of the above
Explanation:- Cytokines interleukin IL-3, IL-6 & IL-11 stimulate platelet production in acute inflammation.
126 Mechanism of thrombocytopenia include ?
A. Decreased bone marrow production
B. Increased splenic sequestration
C. Accelerated destruction
D. All of the above
Explanation:- Thrombocytopenia is caused by decreased bone marrow production or increased splenic sequestration or accelerated destruction of platelets.
127 TAR syndrome means ?
A. Thrombocytopenia with absent reticulocytes
B. Thrombocytopenia with absent renin
C. Thrombocytopenia with absent radii
D. Thrombocytopenia with abnormal vessels
Explanation:- Congenital amegakaryocytic hypoplasia & thrombocytopenia with absent radii (TAR syndrome) produce a selective decrease in megakaryocyte production.
128 Acute ITP is common in ?
A. Children
B. Adults
C. Elderly
D. All of the above
Explanation:- Acute ITP is a severe thrombocytopenia following recovery from a viral exanthem or upper respiratory illness. It is common in children & is responsible 90% of pediatric cases of immunologic thrombocytopenia. >90% cases recover within 3 to 6 months.
129 Which of the following appear in the red cells of asplenic individuals ?
A. Macroovalocytes
B. Basophilic stippling
C. Howell-Jolly bodies
D. Target cells
Explanation:- Howell-Jolly bodies are tiny nuclear remnants that are normally removed by spleen. They appear in blood after splenectomy & with maturation / dysplastic disorders.
130 Rituximab is what type of a monoclonal antibody ?
A. Anti-CD19
B. Anti-CD20
C. Anti-CD21
D. Anti-CD22
Explanation:- Rituximab is an anti-CD20 monoclonal antibody. Efficacy is established in ITP. It eliminates normal B cells that produce antiplatelet antibody.
