Hematology MCQs with Answer and Explanations | Chapter 5

Answer: A & B Both

Megaloblastic anemia can occur in both Vitamin B12 deficiency and Folic Acid deficiency. These are types of anemia characterized by the presence of large, abnormal red blood cells (megaloblasts) in the bone marrow. Both Vitamin B12 and Folic Acid are essential for the synthesis of DNA, and their deficiencies can result in impaired DNA synthesis, leading to the formation of abnormally large red blood cells.

Incorrect Options:

1. Vitamin B12 Deficiency:
   • Megaloblastic anemia occurs in Vitamin B12 deficiency, so this option is incorrect.
2. Folic Acid Deficiency:
   • Megaloblastic anemia occurs in Folic Acid deficiency, so this option is incorrect.
3. Iron Deficiency:
   • Iron deficiency does not typically lead to megaloblastic anemia. Iron deficiency anemia is characterized by small and pale red blood cells, not large ones.

Answer: Factor-Viii

Hemophilia is a genetic disorder characterized by insufficient clotting factors in the blood, leading to prolonged bleeding. In hemophilia A, which is the most common type, there is a deficiency or absence of Factor VIII, a crucial protein involved in the blood clotting process.

The other options are incorrect:

• Factor II: While also crucial for blood clotting, deficiency in Factor II causes a different condition called Prothrombin deficiency, not hemophilia.
• Factor IX: Deficiency in Factor IX leads to Hemophilia B, another type of hemophilia but distinct from the most common form associated with Factor VIII deficiency.
• Factor XI: Factor XI deficiency results in a less common bleeding disorder called Hemophilia C.

Answer: Iron

Purssian blue stain, also known as Prussian blue stain, is commonly used in histology and microscopy to detect the presence of iron. It forms a blue complex with ferric iron, making it visible under a microscope.

The other options are incorrect:

• Hemosidrin: While hemosiderin is a protein that stores iron, the Prussian blue stain doesn’t directly target it. Instead, it detects the iron itself within hemosiderin.
• Glycogen: Glycogen is a carbohydrate used for energy storage and is not related to iron or the Prussian blue staining process.
• Bacteria: Prussian blue stain is not used to identify bacteria. Different staining techniques are employed for bacterial detection.

Answer: Hayem’s Solution

Hayem’s solution is used for the counting of leukocytes (white blood cells) in hematology. It contains mercuric chloride, which acts as a preservative, and potassium iodide, which lyses red blood cells, leaving behind leukocytes for counting.

The other options are incorrect:

• Turk’s Fluid: Turk’s fluid is not used for the counting of leukocytes. It is a fixative solution used for staining blood smears to visualize various blood cell components.
• Dacie Formal Solution: Dacie formal solution is not used for counting leukocytes. It is used for the staining of blood films to visualize blood cell morphology.
• 1% of Ammonium oxalate: Ammonium oxalate solution is not used for leukocyte counting. It is used as an anticoagulant for blood samples, particularly for crystalloid plasma preservation, but not for leukocyte counting.

Answer: Glanzmann Thrombasthenia

Glanzmann thrombasthenia is a rare inherited bleeding disorder caused by a deficiency or dysfunction of the glycoprotein IIb/IIIa receptor on platelets. This receptor is crucial for platelet aggregation, which is necessary for the formation of blood clots to stop bleeding.

The other options are incorrect:

• Bernal Soliuer Syndrome: There is no known disease called Bernal Soliuer Syndrome related to platelet disorders.
• Plt Gray syndrome: Plt Gray syndrome does not exist as a recognized medical condition related to platelet disorders.
• Thrombocytopenia: Thrombocytopenia is a condition characterized by a low platelet count in the blood. While it is a disorder related to platelets, it is not caused specifically by a lack of GP IIb/IIIa receptor on platelets.

Answer: Absent of beta gene

Cooley’s anemia, also known as beta-thalassemia major, is an inherited blood disorder characterized by the reduced or absent production of beta-globin chains, which are essential components of hemoglobin. This results from mutations in the beta-globin gene (HBB gene), leading to ineffective erythropoiesis and severe anemia.

The other options are incorrect:

• Absent of RBC’s: While Cooley’s anemia causes a significant decrease in red blood cell production, it doesn’t completely eliminate them.
• Absent of all blood cells: Cooley’s anemia specifically affects red blood cells and doesn’t impact the production of other types of blood cells like white blood cells or platelets.
• Increase of WBC: Cooley’s anemia leads to decreased red blood cell production, not an increase in white blood cells.

Answer: dehydrate

In a hypertonic solution, the concentration of solutes outside the cell is higher than inside the cell. As a result, water molecules move out of the cell through osmosis, leading to cell dehydration. This causes the cell to shrink or crenate as it loses water.

The other options are incorrect:

• Swell and burst: This is incorrect. Cells in a hypotonic solution swell and may burst due to the influx of water.
• Hemolyze: Hemolysis occurs when red blood cells burst, typically in a hypotonic solution where water enters the cell, causing it to swell and eventually rupture. It is not characteristic of cells in a hypertonic solution.
• Not be affected: This is incorrect. Cells in a hypertonic solution will be affected by dehydration due to the osmotic movement of water out of the cell.

Answer: EDTA blood

EDTA (ethylenediaminetetraacetic acid) is an anticoagulant commonly used for blood cell counts, including red blood cell (RBC) counts. It prevents clotting by chelating calcium ions, thus preserving the morphology and integrity of blood cells, including RBCs, for accurate counting.

The other options are incorrect:

• Citrated blood: Citrated blood is commonly used for coagulation tests as citrate binds calcium, preventing blood clotting. However, it is not suitable for RBC counts as it alters the morphology of blood cells.
• Heparinized blood: Heparin is another anticoagulant used to prevent blood clotting, but it is not typically used for RBC counts. Heparin can interfere with cell morphology and counting accuracy.
• Oxalated blood: Oxalate is an anticoagulant that prevents clotting by precipitating calcium. While it can be used for certain laboratory tests, it is not commonly used for RBC counts and may affect cell morphology and counting accuracy.

Answer: biconcave disc

This accurately describes the shape of a normal, healthy red blood cell (erythrocyte). It has a flattened, disc-like shape with indentations on both sides, resembling a doughnut without a hole.

The other options are incorrect:

• Spherocyte: Spherocytes are abnormally round red blood cells with reduced or absent central pallor. They are typically seen in conditions such as autoimmune hemolytic anemia and hereditary spherocytosis.
• Polymorphonucleocyte: This term is not correct in describing the shape of a normal erythrocyte. “Polymorphonucleocyte” typically refers to a type of white blood cell, specifically a neutrophil, characterized by a multilobed nucleus.
• Thin column: This description does not accurately depict the shape of a normal erythrocyte. Erythrocytes are not columnar; they have a biconcave disc shape.

Answer: plasma, buffy coat, RBC

Heparin is an anticoagulant that prevents blood clotting. Therefore, when a blood sample collected in a heparinized tube is centrifuged, it will separate into plasma (liquid portion) containing blood cells (RBCs) and a buffy coat (thin layer of white blood cells and platelets).

The other options are incorrect:

• Serum and clot: Serum is obtained only after blood clots and the clot retracts, releasing the serum. Heparin prevents clotting, so serum won’t be present.
• Serum and plasma: Plasma is the liquid portion of blood with all its components, while serum is plasma minus clotting proteins. Heparinized blood won’t have clotting proteins, so it’s just plasma.

Answer: erythrocyte sedimentation rate

The Westergren tube is specifically designed to measure the erythrocyte sedimentation rate (ESR), which assesses the rate at which red blood cells (RBCs) settle in a blood sample over time.

The other options are incorrect:

• Hematocrit: This test measures the percentage of red blood cells in whole blood, not the sedimentation rate.
• Reticulocyte count: This test determines the percentage of immature red blood cells, not the sedimentation rate of mature red blood cells.
• Microhematocrit: This is a variation of the hematocrit test using a smaller blood sample, but it still measures the red blood cell concentration, not the sedimentation rate.

Answer: determine the proportions of WBC’s in whole blood

A differential (or differential white blood cell count) is performed to determine the percentages of different types of white blood cells (WBCs) in a blood sample, aiding in the diagnosis of various conditions such as infections, inflammation, and leukemia.

The other options are incorrect:

• Determine the proportion of RBC in whole blood: This is incorrect because the purpose of a differential is to analyze white blood cells, not red blood cells.
• Count the number of WBCs in whole blood: This is incorrect because while a total white blood cell count is part of a complete blood count (CBC), the differential specifically looks at the proportions of different types of white blood cells, not just the total count.
• Diagnose anemia: This is incorrect because while a complete blood count (CBC) may indicate the presence of anemia by measuring red blood cell parameters such as hemoglobin and hematocrit, the differential is focused on white blood cell analysis, not red blood cells.

Answer: ensure even distribution of all blood components

Thoroughly mixing blood samples before testing ensures that all components, including red and white blood cells, platelets, and plasma, are evenly distributed throughout the sample, providing accurate and representative results.

The other options are incorrect:

• Prevent the clumping of platelets: This is incorrect because while mixing prevents platelet clumping, the primary purpose is to evenly distribute all blood components, not specifically to prevent platelet clumping.
• Prevent the formation of small clots: This is incorrect because mixing helps prevent the formation of fibrin clots but doesn’t directly address small clots. The main goal is to ensure uniform distribution of blood components.
• Oxygenate the sample: This is incorrect because mixing doesn’t directly oxygenate the sample; oxygenation occurs through respiration in the body. The primary purpose of mixing is to distribute blood components evenly.

Answer: changes in cell electrical currents

Automated hematology cell counters use the principle of detecting changes in the electrical properties of cells as they pass through a sensing zone, which allows for the quantification and differentiation of different types of blood cells.

The other options are incorrect:

• Diffusion: This is incorrect because automated hematology cell counters do not rely on diffusion; they detect cells based on their electrical properties as they pass through a sensing zone.
• Color absorption changes: This is incorrect because while some laboratory tests may rely on color changes for detection, automated hematology cell counters primarily use electrical impedance or flow cytometry techniques, not color absorption changes.
• High frequency sound waves: This is incorrect because although some medical imaging techniques use sound waves (such as ultrasound), automated hematology cell counters primarily rely on electrical impedance or flow cytometry, not sound waves.

Answer: hemolysis

Hemolysis refers to the breakdown of red blood cells (erythrocytes), releasing their contents, including hemoglobin, into the surrounding environment.

The other options are incorrect:

• Hemorrhage: This refers to bleeding, which involves the loss of blood from the circulatory system, not the destruction of red blood cells within the system.
• Hemostasis: This is the process of stopping bleeding, the opposite of hemolysis.
• Erythropoiesis: This refers to the production of red blood cells, a process distinct from their destruction.

Answer: the angle of the spreader is too low

If the angle of the spreader (such as a slide) is too low when making a blood smear, it can result in a thin smear because the blood is not evenly distributed across the slide.

The other options are incorrect:

• The angle of the spreader is too high: This would create a thicker smear, not a thinner one.
• The edge of the spreader is cracked: While a cracked spreader might affect the smoothness of the smear, it wouldn’t necessarily make it too thin.
• The smear is spread too slowly: Spreading too slowly can affect the overall quality of the smear, but it wouldn’t directly cause it to be too thin.

Answer: Hgb

Hemoglobin (Hgb) is the primary protein in red blood cells responsible for binding and transporting oxygen throughout the body. Therefore, the Hemoglobin test directly measures the oxygen-carrying capacity of RBCs.

The other options are incorrect:

• CBC (Complete Blood Count): While a CBC provides various blood cell information, including RBC count, it doesn’t directly measure the oxygen-carrying capacity, which is primarily determined by hemoglobin concentration.
• Hct (Hematocrit): This test measures the percentage of red blood cells in whole blood, which indirectly reflects oxygen-carrying potential, but it’s not a direct measurement of hemoglobin concentration.
• ESR (Erythrocyte Sedimentation Rate): This test assesses the rate at which red blood cells settle, not their oxygen-binding capacity.

Answer: band cell

An immature neutrophil is most commonly called a band cell. It has a characteristic band-shaped nucleus when observed under a microscope, distinguishing it from a fully mature segmented neutrophil.

The other options are incorrect:

• Blast cell: This refers to a very early stage of development for various blood cell types, not specifically neutrophils.
• LE cell: This is a specific type of abnormal white blood cell associated with lupus.
• Reticulocyte: This refers to an immature red blood cell, not a neutrophil.

Answer: reticulocyte count

The reticulocyte count specifically measures the percentage of immature red blood cells, reticulocytes, present in a blood sample.

The other options are incorrect:

• Osmotic fragility test: This test assesses the fragility of red blood cells in hypotonic solutions, not their immaturity.
• Differential: This test provides a count and proportion of different mature white blood cells, not immature red blood cells.
• RBC count: This test determines the total number of red blood cells, not specifically focusing on immature ones.

Answer: ACTH

ACTH (Adrenocorticotropic Hormone) is a hormone produced by the pituitary gland, primarily regulating stress response and cortisol production. It is not directly involved in monitoring blood clotting mechanisms.

The other options are incorrect:

• PT (Prothrombin Time): This test measures the time it takes for blood to clot, assessing the extrinsic pathway and common pathway of the coagulation cascade.
• APTT (Activated Partial Thromboplastin Time): This test evaluates the intrinsic pathway and common pathway of blood clotting.
• FDP (Fibrin Degradation Products): These are breakdown products of fibrin, a protein essential for blood clot formation. Measuring FDP levels helps assess the extent of fibrinolysis (clot breakdown) and can indirectly indicate abnormalities in the coagulation process.

Answer: 7.2 μm

The average diameter of a red blood cell (RBC) is approximately 7.2 micrometers (μm).

The other options are incorrect:

• 1 μm: This is significantly smaller than the typical diameter of an RBC.
• 8 μm: This is slightly larger than the average diameter of an RBC.
• 6.5 μm: This is slightly smaller than the average diameter of an RBC.

Answer: 0.2 – 2 %

The normal range of reticulocytes in the blood is typically 0.2 – 2%.

The other options are incorrect:

1. 2-4%: This is incorrect because 2-4% is too high for the normal range of reticulocytes; levels above 2% may indicate increased red blood cell production.
2. 2.2 – 4.4%: This is incorrect because 2.2 – 4.4% is also too high for the normal range of reticulocytes; levels above 2% may indicate increased red blood cell production.
3. 1-2%: This is incorrect because 1-2% is too low for the normal range of reticulocytes; levels below 0.2% may indicate decreased red blood cell production.

Answer: 3.8% Tri-Sodium Citrate

3.8% Tri-Sodium Citrate is the anticoagulant used in the Westergren’s method for erythrocyte sedimentation rate (ESR) testing.

The other options are incorrect:

• EDTA: EDTA is commonly used as an anticoagulant in blood collection tubes for routine hematological testing, but it is not typically used in the Westergren’s method for ESR testing.
• Heparin: heparin is another anticoagulant commonly used in blood collection tubes, but it is not typically used in the Westergren’s method for ESR testing.
• Any of above: while EDTA and heparin are commonly used anticoagulants in blood collection tubes, the specific anticoagulant used in the Westergren’s method for ESR testing is 3.8% Tri-Sodium Citrate.

Answer: 3 lobs

Neutrophils typically have 3 lobes in their nucleus.

The other options are incorrect:

• 5 lobs: neutrophils normally have 3 lobes in their nucleus, not 5.
• 6 lobs: neutrophils typically have 3 lobes in their nucleus, not 6.
• No lobs: Tneutrophils do have lobes in their nucleus, though the number can vary. The typical number is 3, but it can range from 2 to 5.

Answer: Serum

Serum is plasma without fibrinogen and other clotting factors, obtained by allowing blood to clot and then removing the clot and the clotting factors.

The other options are incorrect:

• Blood: blood refers to the fluid circulating in the cardiovascular system, which includes both plasma and formed elements such as red blood cells, white blood cells, and platelets.
• Plasma: plasma contains fibrinogen and other clotting factors; plasma without fibrinogen is called serum.
• Water: water does not contain the proteins and other components found in plasma or serum.

Answer: Platelet

Megakaryocytes are the precursors of platelets, tiny cell fragments essential for blood clotting.

The other options are incorrect:

• RBC (Red Blood Cell): Megakaryocytes are a different cell lineage than RBCs, which are produced from separate precursor cells.
• WBC (White Blood Cell): WBCs encompass various types of immune cells, distinct from the platelet-producing megakaryocytes.
• Plasma Cell: Plasma cells are specialized immune cells derived from B lymphocytes, not related to megakaryocytes.

Answer: Reduction of all type of blood cells

Pancytopenia is a condition characterized by a reduction in the number of all types of blood cells, including red blood cells, white blood cells, and platelets.

The other options are incorrect:

• Low number of RBC: pancytopenia involves a reduction in all types of blood cells, not just red blood cells.
• Increasing of all type of blood cells: pancytopenia involves a decrease, not an increase, in all types of blood cells.
• Reduction in cytoplasmic Ratio: cytoplasmic ratio refers to the proportion of cytoplasm to nucleus in a cell, and pancytopenia is characterized by a decrease in blood cell numbers, not changes in cellular morphology.

Answer: Kupffer cells

Kupffer cells are specialized phagocytic cells found in the liver, responsible for clearing debris and pathogens from the blood.

The other options are incorrect:

• Neutrophils: neutrophils are a type of white blood cell found in the bloodstream and are not specific to the liver.
• Lymphocytes: lymphocytes are a type of white blood cell involved in immune responses and are not specific to the liver.
• Macrophage: while macrophages are phagocytic cells found throughout the body, including the liver, Kupffer cells specifically refer to the phagocytic cells of the liver.

Answer: RBC

The lifespan of red blood cells (RBCs) is approximately 4 months before they are removed by the spleen and liver.

Incorrect Options:

• WBC: This is incorrect because the lifespan of white blood cells (WBCs) varies depending on the type, ranging from a few hours to several days.
• Platelet: This is incorrect because the lifespan of platelets is much shorter, typically around 7-10 days.
• Neutrophils: This is incorrect because neutrophils, a type of white blood cell, have a lifespan of only a few hours to a few days.

Answer: Fibrin stabilizing factor

Factor XIII is also known as fibrin stabilizing factor because it plays a crucial role in cross-linking fibrin strands to form a stable blood clot.

The other options are incorrect:

• Fibrinogen: This is incorrect because fibrinogen is a precursor protein that is converted to fibrin during the clotting cascade, but it is not another name for factor XIII.
• Anti-Hemophilic factor: This is incorrect because anti-hemophilic factor refers to factor VIII, which is deficient in individuals with hemophilia A.
• Calcium: This is incorrect because calcium is a mineral cofactor required for several steps in the clotting cascade, but it is not another name for factor XIII.

Answer: Factor – IX

Haemophilia V, also known as parahemophilia, is caused by a deficiency in Factor IX, a clotting factor involved in the intrinsic pathway of the coagulation cascade.

The other options are incorrect:

• Factor – VIII: Factor VIII deficiency is known as hemophilia A, not hemophilia V.
• Factor – II: Factor II deficiency is known as afibrinogenemia, not hemophilia V.
• Factor – XI: Factor XI deficiency is known as hemophilia C, not hemophilia V.

Answer: APTT

Activated Partial Thromboplastin Time (APTT) is the test used to measure the intrinsic pathway of the coagulation cascade, which includes factors XII, XI, IX, VIII, and X.

The other options are incorrect:

• PT: This is incorrect because the prothrombin time (PT) measures the extrinsic pathway of the coagulation cascade, which involves factors outside of the intrinsic pathway.
• TT: This is incorrect because the thrombin time (TT) measures the conversion of fibrinogen to fibrin and evaluates the activity of the final step in the coagulation cascade, not specifically the intrinsic pathway.
• Fibrinolysis: This is incorrect because fibrinolysis refers to the process of breaking down fibrin clots, which occurs after the completion of the coagulation cascade, not specifically the intrinsic pathway.

Answer: CD4

In HIV-positive patients, the number of CD4+ T cells, also known as helper T cells, decreases due to the direct targeting of these cells by the virus, leading to immune system dysfunction.

The other options are incorrect:

• CD8: while CD8+ T cells, also known as cytotoxic T cells, are involved in the immune response against HIV, their numbers may increase rather than decrease during the early stages of infection.
• Small Lymphocyte: small lymphocytes include various types of white blood cells, such as T cells, B cells, and natural killer (NK) cells. While some subsets of small lymphocytes may decrease in HIV-positive patients, the specific decrease is primarily observed in CD4+ T cells.
• All of above: while CD4+ T cells are decreased in HIV-positive patients, the decrease is not observed in all blood cell types.

Answer: Plasmodium falciparum

Cerebral malaria, a severe form of malaria associated with neurological complications, is primarily caused by infection with the Plasmodium falciparum parasite, which is known for its ability to sequester in the microvasculature of the brain.

The other options are incorrect:

• Plasmodium Vivax: This is incorrect because while Plasmodium vivax can cause malaria, it is not typically associated with the severe neurological complications seen in cerebral malaria.
• Plasmodium Ovale: This is incorrect because Plasmodium ovale can cause malaria, but it is not typically associated with the severe neurological complications seen in cerebral malaria.
• All of above: This is incorrect because cerebral malaria is primarily caused by infection with Plasmodium falciparum, not all species of Plasmodium.

Answer: All of above

Megaloblastic anemia occurs due to deficiencies in either folate (vitamin B9) or vitamin B12. Both these vitamins play crucial roles in DNA synthesis, which is essential for the proper development and maturation of red blood cells. A deficiency in either one disrupts this process, leading to the production of abnormally large and dysfunctional red blood cells, characteristic of megaloblastic anemia.111

Answer: Hematoma

A hematoma is a localized collection of blood outside the blood vessels, often appearing as a solid mass under the skin at the site of venepuncture or injury.

The other options are incorrect:

• Sarcoma: A sarcoma is a type of cancer that arises from the cells of mesenchymal origin, such as bone, cartilage, fat, or muscle, and it is not related to a subcutaneous mass of blood.
• Bleeding: bleeding refers to the process of blood escaping from blood vessels, not the collection of blood outside vessels that forms a hematoma.
• Hemolysis: hemolysis refers to the rupture or destruction of red blood cells, leading to the release of hemoglobin into the surrounding fluid, and it is not related to the formation of a hematoma.

Answer: Fibrinolysis

Fibrinolysis is the process of breaking down fibrin clots after they have served their purpose in blood clotting. It is involved in clot resolution and preventing excessive clot formation.

The other options are incorrect:

• Platelet: Platelets play a crucial role in blood clotting by adhering to the site of injury, aggregating to form a plug, and releasing factors that promote clot formation.
• Clotting Factor: Clotting factors are proteins in the blood that are essential for the formation of blood clots. They are directly involved in the clotting cascade, leading to the formation of fibrin clots.
• Vasoconstriction: Vasoconstriction is the narrowing of blood vessels in response to injury or other stimuli. It helps reduce blood loss by decreasing blood flow to the injured area and promoting clot formation.
• a

Answer: Embolism

An embolism occurs when a blood clot (or other material such as fat, air, or a foreign body) breaks loose and travels through the bloodstream to another part of the body, potentially causing blockage of a blood vessel.

The other options are incorrect:

• Vector: A vector is an organism that transmits infectious pathogens from one host to another, such as a mosquito transmitting malaria parasites. It is not related to the movement of blood clots.
• Hematoma: A hematoma is a localized collection of blood outside the blood vessels, typically appearing as a solid mass under the skin at the site of injury, not related to the movement of blood clots.
• Thrombus: Athrombus is a blood clot that forms and remains attached to the wall of a blood vessel. It is not the term used to describe a blood clot that is moving throughout the body.

Answer: Factor- XIII

Factor XIII is a clotting factor that plays a crucial role in stabilizing the fibrin clot by cross-linking fibrin strands, making the clot more resistant to breakdown.

The other options are incorrect:

• Factor- I: Factor I is fibrinogen, which is converted into fibrin by the action of thrombin during the clotting cascade. It does not act on the fibrin clot to stabilize it.
• Thrombin: because thrombin is a serine protease that converts fibrinogen to fibrin during the clotting cascade. It is not involved in stabilizing the fibrin clot.
• Prothrombin: prothrombin is the precursor protein to thrombin, which is converted into thrombin during the clotting cascade. It is not involved in stabilizing the fibrin clot.

Answer: Lymphocyte

Lymphocytes are a type of white blood cell that belongs to the agranulocyte category. They lack cytoplasmic granules and have a non-segmented nucleus.

The other options are incorrect:

• a
• Basophil: Basophils are a type of granulocyte characterized by the presence of large granules that stain blue-purple with basic dyes.
• Neutrophil: Neutrophils are a type of granulocyte characterized by the presence of fine granules that stain pale lilac with neutral dyes.
• Eosinophil: Eosinophils are a type of granulocyte characterized by the presence of large granules that stain red-orange with acidic dyes.

Answer: Indirect Coombs test

The Indirect Coombs test is used to detect in-vitro sensitization of red blood cells (RBCs) by detecting the presence of antibodies in the serum that react with RBC antigens.

The other options are incorrect:

• Direct Coombs Test: The Direct Coombs test is used to detect antibodies that are already attached to the surface of RBCs, typically in autoimmune hemolytic anemia or hemolytic disease of the newborn.
• Agglutination: while agglutination reactions can occur in both Direct and Indirect Coombs tests, agglutination alone does not specifically detect in-vitro sensitization of RBCs.
• Precipitation: precipitation reactions involve the formation of a solid precipitate when soluble antigens and antibodies combine, but they are not typically used to detect in-vitro sensitization of RBCs.

Answer: Hemopoiesis

Hemopoiesis is the process of blood cell formation, which occurs primarily in the bone marrow.

The other options are incorrect:

• Mitosis: mitosis is a cellular process in which a cell divides to produce two daughter cells with identical genetic material. While mitosis plays a role in the proliferation of blood cells, it is not specifically the process of blood cell formation.
• Photosynthesis: photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll. It is not related to the formation of blood cells.
• Complement fixation: complement fixation is a part of the immune response involving the binding of complement proteins to antigen-antibody complexes, leading to various effector functions. It is not related to the formation of blood cells.

Answer: Reduced

In sickle cell anemia, the red blood cell count is reduced due to the abnormal shape of the red blood cells, which can lead to hemolysis (destruction of red blood cells) and decreased overall red blood cell count.

The other options are incorrect:

• Increased: In sickle cell anemia, the red blood cell count is typically reduced, not increased.
• Normal: sickle cell anemia is characterized by a decreased red blood cell count, so the red blood cell count is not within the normal range.
• None: In sickle cell anemia, there is typically a decrease in red blood cell count, so the option “None” is not accurate.

Answer: 7 micro meter

The size of a typical red blood cell (erythrocyte) is approximately 7 micrometers in diameter.

The other options are incorrect:

• 10 micro meter: 10 micrometers is larger than the typical size of a red blood cell.
• 8 micro meter: while 8 micrometers is closer to the correct size, the typical diameter of a red blood cell is approximately 7 micrometers.
• 2 micro meter: 2 micrometers is smaller than the typical size of a red blood cell.

Answer: Afibrinoginemia

Bleeding time primarily assesses platelet function and the initial stages of clot formation, not involving the later steps dependent on clotting factors.

The other options are incorrect:

• Deficiency of vitamin K: Vitamin K is crucial for the production of certain clotting factors, but its deficiency primarily affects the intrinsic pathway of coagulation, not significantly impacting bleeding time.
• Hemophilia: Hemophilia refers to deficiencies in specific clotting factors (mainly Factor VIII or IX), affecting the later stages of clot formation, not directly impacting bleeding time.
• Thrombocytopenia: This condition, characterized by a low platelet count, significantly disrupts platelet plug formation, leading to prolonged bleeding time.

Answer: Mesoblastic stage

During embryonic life, blood cell development primarily occurs in the mesoblastic stage, which is characterized by the formation of blood islands within the mesoderm layer of the embryo.

The other options are incorrect:

• Hepatic stage: This is incorrect because the hepatic stage refers to the development of blood cells in the liver, which primarily occurs during fetal life, not embryonic life.
• Myeloid stage: This is incorrect because the myeloid stage refers to the development of blood cells in the bone marrow, which occurs later in fetal life and postnatally, rather than during embryonic life.
• Mature stage: This is incorrect because the term “mature stage” is not specific to any particular developmental phase of blood cells.

Answer: Factors V & VIII

Factors V and VIII are known to be unstable at low freezing points, particularly during storage, leading to their degradation. This instability can result in reduced activity levels of these clotting factors.

The other options are incorrect:

• Factors IX & X: Factors IX and X are generally stable at low freezing points and do not exhibit significant degradation during storage.
• Factors IV & V: Factor IV (calcium) is not a clotting factor, and Factor V is unstable at low freezing points, not stable.
• Factors II: Factor II (prothrombin) is generally stable at low freezing points and does not exhibit significant degradation during storage.

Answer: 150,000 450,000 mm3

The normal platelet count in adults typically ranges from 150,000 to 450,000 platelets per cubic millimeter of blood.

The other options are incorrect:

• 100,000 to 300,000 mm3: it represents the lower end of the normal range for platelet count, while the upper limit is missing.
• 150,000 to 250,000 mm3: It represents a narrower range than the typical normal range for platelet count, with both the lower and upper limits being lower than usual.
• 200,000 to 300,000 mm3: It represents a narrower range than the typical normal range for platelet count, with the upper limit being lower than usual.

Answer: Pernicious anemia

Pernicious anemia is caused by a lack of intrinsic factor, a protein produced by the stomach that is necessary for the absorption of vitamin B12. Without intrinsic factor, vitamin B12 deficiency occurs, leading to anemia.

The other options are incorrect:

• Sickle cell anemia: sickle cell anemia is caused by a genetic mutation in hemoglobin, resulting in the production of abnormal hemoglobin molecules that cause red blood cells to become sickle-shaped.
• Target cell anemia: target cell anemia, also known as codocyte formation, is characterized by red blood cells with a bull’s eye appearance due to excess membrane surface area relative to cell volume. It is often associated with conditions such as thalassemia or liver disease.
• Iron deficiency anemia: iron deficiency anemia is caused by a lack of iron in the body, leading to decreased production of hemoglobin and consequently, smaller and paler red blood cells.

Answer: 1 gm%

Transfusion of one unit of fresh blood typically increases the hemoglobin concentration by approximately 1 gram per deciliter (gm%).

The other options are incorrect:

• 0.1 gm%: it represents a much smaller increase in hemoglobin concentration than what is typically observed with the transfusion of one unit of fresh blood.
• 2 gm%: it represents a larger increase in hemoglobin concentration than what is typically observed with the transfusion of one unit of fresh blood.
• 2.2 gm%: it represents an even larger increase in hemoglobin concentration than the previous option, which is not typical for the transfusion of one unit of fresh blood.
• A