1. What is the relation of Hypoxia to EPO production? a) EPO is released from liver into blood in response to Hypoxia b) EPO is released from kidney into blood in response to Hyperoxia c) EPO is released from kidney into blood in response to Hypoxia d) EPO is released from liver into blood in response to Hyperoxia e) EPO is not related to Hypoxia Answer: c) EPO is released from kidney into blood in response to Hypoxia. Explanation: Hypoxia triggers the release of EPO from the kidney into the bloodstream, which stimulates erythropoiesis. 2. Earliest recognizable stage in Erythropoiesis is? a) Reticulocyte b) Polychromatophilic normoblast c) Orthochromatophilic normoblast d) Basophilic normoblast e) Erythrocyte Answer: d) Basophilic normoblast. Explanation: The earliest recognizable stage in erythropoiesis is the basophilic normoblast, which is a precursor cell that gives rise to all other erythrocyte precursors. 3. Hemoglobin production in Erythropoiesis starts at what stage? a) Reticulocyte b) Polychromatophilic normoblast c) Orthochromatophilic normoblast d) Basophilic normoblast e) Erythrocyte Answer: d) Basophilic normoblast. Explanation: Hemoglobin production in erythropoiesis starts at the basophilic normoblast stage, where the cell begins to synthesize hemoglobin. 4. Hemoglobin production in Erythropoiesis ends at what stage? a) Reticulocyte b) Polychromatophilic normoblast c) Orthochromatophilic normoblast d) Basophilic normoblast e) Erythrocyte Answer: a) Reticulocyte. Explanation: Hemoglobin production in erythropoiesis ends at the reticulocyte stage, where the cell expels its nucleus and becomes a mature erythrocyte. 5. What is the last stage in Erythropoiesis that is capable of Mitosis? a) Reticulocyte b) Polychromatophilic normoblast c) Orthochromatophilic normoblast d) Basophilic normoblast e) Erythrocyte Answer: b) Polychromatophilic normoblast. Explanation: The polychromatophilic normoblast is the last stage in erythropoiesis that is capable of mitosis, meaning it can still divide and produce more precursor cells. 6. What is the last stage in Erythropoiesis with a nucleus? a) Reticulocyte b) Polychromatophilic normoblast c) Orthochromatophilic normoblast d) Basophilic normoblast e) Erythrocyte Answer: c) Orthochromatophilic normoblast. Explanation: The orthochromatophilic normoblast is the last stage in erythropoiesis with a nucleus, as it expels its nucleus during the final stages of maturation. 7. The first non-nucleated precursor of red blood cell in Erythropoiesis is? a) Reticulocyte b) Polychromatophilic normoblast c) Orthochromatophilic normoblast d) Basophilic normoblast e) Erythrocyte Answer: a) Reticulocyte. Explanation: The reticulocyte is the first non-nucleated precursor of red blood cells in erythropoiesis, as it has expelled its nucleus and is on its way to becoming a mature erythrocyte. 1. What did Anton van Leeuwenhoek give an account of in 1674? a) Platelets b) Hematopoiesis c) Red blood cells d) Microsampling e) None of the above Answer: c) Red blood cells. Explanation: Anton van Leeuwenhoek gave an account of red blood cells in 1674. 2. Who described platelets as "petites plaques" in the 1800s? a) Anton van Leeuwenhoek b) Giulio Bizzozero c) James Homer Wright d) Mesoblastic phase e) None of the above Answer: b) Giulio Bizzozero. Explanation: Giulio Bizzozero described platelets as "petites plaques" in the 1800s. 3. What did James Homer Wright develop in 1902? a) Hematopoiesis b) Microsampling c) Platelets d) Wright stain e) None of the above Answer: d) Wright stain. Explanation: James Homer Wright developed the Wright stain in 1902. 4. What is the common anticoagulant used in Hematology? a) EDTA b) Sodium Citrate c) Heparin d) All of the above e) None of the above Answer: d) All of the above. Explanation: EDTA, Sodium Citrate, and Heparin are all common anticoagulants used in Hematology. 5. What is the mode of action of Heparin? a) Forms calcium salts to remove calcium b) Helps platelets maintain their functional capabilities c) Interacts with antithrombin d) Inactivates thrombin and thromboplastin e) None of the above Answer: c) Interacts with antithrombin. Explanation: Heparin interacts with antithrombin, inactivates thrombin and thromboplastin. 6. What is the order of draw for micro collection tubes? a) Gold top, Other micro collection tubes, EDTA b) Other micro collection tubes, Gold top, EDTA c) EDTA, Other micro collection tubes, Gold top d) EDTA, Gold top, Other micro collection tubes e) None of the above Answer: c) EDTA, Other micro collection tubes, Gold top. Explanation: The order of draw for micro collection tubes is EDTA, Other micro collection tubes, Gold top. 7. What is the site of collection for infants in microsampling? a) Less than one year old b) Child or adult c) Both a and b d) Neither a nor b e) None of the above Answer: a) Less than one year old. Explanation: The site of collection for infants in microsampling is less than one year old. 8. What is hematopoiesis? a) A process of blood cell production b) A process of blood cell destruction c) A process of blood cell transformation d) A process of blood cell transportation e) None of the above Answer: a) A process of blood cell production. Explanation: Hematopoiesis is a continuous, regulated process of blood cell production that includes cell renewal, proliferation, differentiation, and maturation. 9. What is the phase of intrauterine hematopoiesis? a) Mesoblastic phase b) Endodermal phase c) Ectodermal phase d) All of the above e) None of the above Answer: a) Mesoblastic phase. Explanation: The phase of intrauterine hematopoiesis is the mesoblastic phase. 1. In which phase of intrauterine hematopoiesis does the development of primitive erythroblasts occur? A. Myeloid or Medullary B. Hepatic C. Mesoblastic D. Lymphoid E. None of the above Answer: C. Mesoblastic Explanation: The mesoblastic phase of intrauterine hematopoiesis occurs on the 19th day of gestation and is the chief site for the development of primitive erythroblasts. 2. Which site is the chief site for the development of erythroblasts, granulocytes, and monocytes during intrauterine hematopoiesis? A. Myeloid or Medullary B. Hepatic C. Mesoblastic D. Lymphoid E. None of the above Answer: B. Hepatic Explanation: The hepatic phase of intrauterine hematopoiesis occurs during the 4-5th week of gestation and is the chief site for the development of erythroblasts, granulocytes, and monocytes. Alpha and gamma globin chain predominates during this phase. 3. During which phase of intrauterine hematopoiesis is mainly producing granulocytes? A. Myeloid or Medullary B. Hepatic C. Mesoblastic D. Lymphoid E. None of the above Answer: A. Myeloid or Medullary Explanation: The myeloid or medullary phase of intrauterine hematopoiesis occurs during the 5th month of gestation and is the chief site for mainly producing granulocytes. The M:E ratio is 3:1 or 4:1 during this phase. 4. Which of the following is not a main site of adult hematopoiesis? A. Ribs B. Skull, sternum, shoulder blades C. Vertebrae D. Pelvis and proximal ends of long bones E. Liver Answer: E. Liver Explanation: The main sites of adult hematopoiesis are Ribs, Skull, sternum, shoulder blades, Vertebrae, and Pelvis and proximal ends of long bones. The liver is part of the reticuloendothelial system and can play a role in hematopoiesis in certain situations. 5. What is the role of cytokines in hematopoiesis? A. Inhibit apoptosis B. Stimulate or inhibit producing, differentiating, and trafficking of mature blood cells and their precursor C. Promote cell renewal D. Increase proliferation E. None of the above Answer: B. Stimulate or inhibit producing, differentiating, and trafficking of mature blood cells and their precursor Explanation: Cytokines play a crucial role in hematopoiesis by stimulating or inhibiting the production, differentiation, and trafficking of mature blood cells and their precursor. Interleukin, lymphokines, monokines, interferons, and colony-stimulating factors are examples of cytokines. 6. What is the role of growth factors in hematopoiesis? A. Inhibit apoptosis B. Stimulate or inhibit producing, differentiating, and trafficking of mature blood cells and their precursor C. Promote cell renewal D. Increase proliferation E. None of the above Answer: D. Increase proliferation Explanation: Growth factors play a crucial role in hematopoiesis by increasing the proliferation of hematopoietic stem cells and their progenitors. They can also promote cell survival and differentiation. 1. What is the role of growth factors in hematopoiesis? a) Induce apoptosis of cells b) Inhibit apoptosis of cells c) Promote cell differentiation d) Decrease cell proliferation e) None of the above Answer: b) Inhibit apoptosis of cells. Growth factors play a crucial role in hematopoiesis by inhibiting apoptosis of cells. 2. What is the function of erythropoietin in erythropoiesis? a) Induce apoptosis of cells b) Inhibit apoptosis of cells c) Promote cell differentiation d) Decrease cell proliferation e) None of the above Answer: c) Promote cell differentiation. Erythropoietin serves as a differentiation factor causing CFU-E to differentiate into pronormoblast. 3. What is the relation of hypoxia to EPO production? a) Hypoxia decreases EPO production b) Hypoxia increases EPO production c) Hypoxia has no effect on EPO production d) EPO production is not related to hypoxia e) None of the above Answer: b) Hypoxia increases EPO production. Hypoxia stimulates the production of erythropoietin, which in turn promotes erythropoiesis. 4. What are the criteria used in the identification of erythroid precursors? a) Nuclear diameter and cytoplasmic color b) Nuclear chromatin pattern and presence of nucleoli c) N:C ratio and overall diameter of cell d) All of the above e) None of the above Answer: d) All of the above. The criteria used in the identification of erythroid precursors include nuclear diameter, nuclear chromatin pattern, presence of nucleoli, N:C ratio, overall diameter of cell, and cytoplasmic color. 5. What is the size of a pronormoblast? a) 1-2 µm b) 12-20 µm c) 20-30 µm d) 30-40 µm e) None of the above Answer: b) 12-20 µm. A pronormoblast is a precursor of red blood cells and has a size of 12-20 µm. e size of a polychromatophilic normoblast? ■What is the cytoplasmic color of an orthochromic normoblast? Answers: - The earliest recognizable stage is the pronormoblast. - Hb production starts at the polychromatophilic normoblast stage. - Hb production ends at the orthochromic normoblast stage. - The size of a polychromatophilic normoblast is 10-12 µm. - The cytoplasmic color of an orthochromic normoblast is more pinkish. Explanation: These questions are based on the different stages of erythropoiesis, the process of red blood cell formation. The questions test the knowledge of the size, shape, and characteristics of each stage, as well as the timing of hemoglobin production. The answers provide a brief explanation of each stage and its characteristics. 1. What percentage of RBCs die every day? a) 10% b) 20% c) 30% d) 40% e) 50% Answer: c) 30% Explanation: Approximately 30% of RBCs die every day and are replaced by new ones. 2. At what stage does the earliest recognizable stage of RBCs occur? a) Proerythroblast b) Basophilic erythroblast c) Polychromatic erythroblast d) Orthochromatic erythroblast e) Reticulocyte Answer: a) Proerythroblast Explanation: The earliest recognizable stage of RBCs is the proerythroblast stage. 3. At what stage does Hb production start? a) Proerythroblast b) Basophilic erythroblast c) Polychromatic erythroblast d) Orthochromatic erythroblast e) Reticulocyte Answer: b) Basophilic erythroblast Explanation: Hb production starts at the basophilic erythroblast stage. 4. At what stage does Hb production end? a) Proerythroblast b) Basophilic erythroblast c) Polychromatic erythroblast d) Orthochromatic erythroblast e) Reticulocyte Answer: d) Orthochromatic erythroblast Explanation: Hb production ends at the orthochromatic erythroblast stage. 5. What is the last stage capable of mitosis? a) Proerythroblast b) Basophilic erythroblast c) Polychromatic erythroblast d) Orthochromatic erythroblast e) Reticulocyte Answer: c) Polychromatic erythroblast Explanation: The polychromatic erythroblast is the last stage capable of mitosis. 6. What is the last stage with a nucleus? a) Proerythroblast b) Basophilic erythroblast c) Polychromatic erythroblast d) Orthochromatic erythroblast e) Reticulocyte Answer: d) Orthochromatic erythroblast Explanation: The orthochromatic erythroblast is the last stage with a nucleus. 7. What is the first non-nucleated red blood cell? a) Proerythroblast b) Basophilic erythroblast c) Polychromatic erythroblast d) Orthochromatic erythroblast e) Reticulocyte Answer: e) Reticulocyte Explanation: The reticulocyte is the first non-nucleated red blood cell. 8. What is hemoglobin? a) A respiratory pigment b) A main component of RBCs c) Has the oxygen and carbon dioxide-carrying capacity of RBCs d) All of the above e) None of the above Answer: d) All of the above Explanation: Hemoglobin is a respiratory pigment, a main component of RBCs, and has the oxygen and carbon dioxide-carrying capacity of RBCs. 9. What is the structure of heme? a) Protophorphyrin IX + Fe2+ b) 4 globin chains in 1 hemoglobin molecule c) 2 identical pairs of unlike polypeptide chains d) All of the above e) None of the above Answer: a) Protophorphyrin IX + Fe2+ Explanation: The structure of heme is protoporphyrin IX + Fe2+. 10. What are the globin chains in hemoglobin? a) 4 globin chains in 1 hemoglobin molecule b) 2 identical pairs of unlike polypeptide chains c) Intrauterine: Gower-1, Gower-2, Portland, HbF2 zeta and 2 epsilon, 2 alpha and 2 epsilon, 2 zeta and 2 gamma, 2 alpha and 2 gamma, Birth: HbF, HbA2 alpha and 2 gamma, 2 alpha and 2 beta, Adulthood: HbF (1-2%), HbA (>95%), HbA2 (3-5%) d) All of the above e) None of the above Answer: b) 2 identical pairs of unlike polypeptide chains Explanation: The globin chains in hemoglobin consist of 2 identical pairs of unlike polypeptide chains, each containing 141 to 146 amino acids. 11. What is oxyhemoglobin? a) Hb not bound but capable of binding Oxygen b) Hb bound to Carbon Monoxide (CO) c) Reversibly bound to Oxygen d) All of the above e) None of the above Answer: c) Reversibly bound to Oxygen Explanation: Oxyhemoglobin is reversibly bound to oxygen. 12. What is carboxyhemoglobin? a) Hb not bound but capable of binding Oxygen b) Hb bound to Carbon Monoxide (CO) c) Reversibly bound to Oxygen d) All of the above e) None of the above Answer: b) Hb bound to Carbon Monoxide (CO) Explanation: Carboxyhemoglobin is Hb bound to Carbon Monoxide (CO). protect RBC from oxidative stress 3. Methemoglobin Reductase Pathway -reduces methemoglobin back to hemoglobin 4. Heme Oxygenase Pathway -breaks down heme into biliverdin, iron, and carbon monoxide A. What is carboxyhemoglobin? 1. Hb not bound but capable of binding Oxygen 2. Hb bound to Carbon Monoxide (CO) 3. Hb bound to sulfur 4. Hb with iron in ferric state 5. Hb with high affinity for oxygen Answer: 2. Hb bound to Carbon Monoxide (CO) Explanation: Carboxyhemoglobin is formed when hemoglobin binds to carbon monoxide instead of oxygen. This can be dangerous as carbon monoxide has a much greater affinity for hemoglobin than oxygen, leading to decreased oxygen delivery to tissues. B. What causes sulfhemoglobin formation? 1. Binding of hemoglobin to carbon monoxide 2. Incorporation of sulfur into heme 3. Presence of iron in ferric state in hemoglobin 4. Multiple transfusions of blood 5. Depletion of 2,3-BPG in hemoglobin Answer: 2. Incorporation of sulfur into heme Explanation: Sulfhemoglobin is formed when sulfur is incorporated into the heme portion of hemoglobin, leading to a green color and spectral absorption peaks at 620 nm. This can be caused by certain medications such as sulfonamides, phenacetin, acetanilide, and phenazopyridine. C. What shifts the oxygen dissociation curve to the right? 1. High affinity for oxygen 2. Depleted 2,3-BPG in hemoglobin 3. Alkalosis 4. Presence of Hb variants 5. Increased body temperature Answer: 5. Increased body temperature Explanation: A shift to the right in the oxygen dissociation curve indicates a lower affinity for oxygen, meaning that oxygen is more readily released to tissues. This can be caused by factors such as increased body temperature, increased levels of CO2, H+, and Cl-, and the presence of abnormal hemoglobins with low affinity for oxygen. D. What is the primary metabolic pathway used by RBCs? 1. Embden-Meyerhof pathway 2. Hexose Monophosphate Shunt 3. Methemoglobin Reductase Pathway 4. Heme Oxygenase Pathway 5. Aerobic glycolysis Answer: 1. Embden-Meyerhof pathway Explanation: The Embden-Meyerhof pathway, also known as anaerobic glycolysis, is the primary metabolic pathway used by RBCs to generate energy in the absence of oxygen. This pathway generates 2 moles of ATP for every glucose molecule broken down to lactic acid. 1. What happens to glucose during anaerobic glycolysis? a) It is converted to pyruvate b) It is converted to lactic acid c) It is converted to acetyl-CoA d) It is converted to ATP e) It is converted to NADH Answer: b) It is converted to lactic acid. Explanation: During anaerobic glycolysis, glucose is broken down into lactic acid. 2. What is the function of the Hexose Monophosphate Shunt? a) Production of ATP b) Production of NADH c) Production of reduced glutathione to prevent denaturation of Hb d) Production of 2,3 DPG e) Production of pyruvate Answer: c) Production of reduced glutathione to prevent denaturation of Hb. Explanation: The Hexose Monophosphate Shunt is involved in the production of reduced glutathione, which helps prevent denaturation of hemoglobin. 3. What is the function of the Rapaport Leubering Pathway? a) Production of ATP b) Production of NADH c) Production of reduced glutathione to prevent denaturation of Hb d) Production of 2,3 DPG e) Production of pyruvate Answer: d) Production of 2,3 DPG. Explanation: The Rapaport Leubering Pathway is involved in the production of 2,3 DPG, which regulates the affinity of the hemoglobin molecule to oxygen. 4. What is the function of Methemoglobin Reductase? a) Production of ATP b) Production of NADH c) Maintenance of the iron present in HB molecule to its reduced state d) Production of 2,3 DPG e) Production of pyruvate Answer: c) Maintenance of the iron present in HB molecule to its reduced state. Explanation: Methemoglobin Reductase is responsible for maintaining the iron present in the hemoglobin molecule to its reduced state. 5. What is the characteristic of normochromic RBCs? a) They have a central area of pallor greater than 3 µm b) They are gray-blue in color and usually larger than normal red cells c) They have less than the normal amount of hemoglobin d) They have a well hemoglobinized cytoplasm with a small but distinct zone of central pallor e) They have a decreased surface-to-volume ratio and a decreased or absent central pallor Answer: d) They have a well hemoglobinized cytoplasm with a small but distinct zone of central pallor. Explanation: Normochromic RBCs have a normal color and a well hemoglobinized cytoplasm with a small but distinct zone of central pallor that does not exceed 3 µm when measured linearly. 6. What is the characteristic of hypochromic RBCs? a) They have a central area of pallor greater than 3 µm b) They are gray-blue in color and usually larger than normal red cells c) They have less than the normal amount of hemoglobin d) They have a well hemoglobinized cytoplasm with a small but distinct zone of central pallor e) They have a decreased surface-to-volume ratio and a decreased or absent central pallor Answer: c) They have less than the normal amount of hemoglobin. Explanation: Hypochromic RBCs have a central area of pallor greater than 3 µm and have less than the normal amount of hemoglobin. 7. What is the characteristic of hyperchromic RBCs? a) They have a central area of pallor greater than 3 µm b) They are gray-blue in color and usually larger than normal red cells c) They have less than the normal amount of hemoglobin d) They have a well hemoglobinized cytoplasm with a small but distinct zone of central pallor e) They have a decreased surface-to-volume ratio and a decreased or absent central pallor Answer: e) They have a decreased surface-to-volume ratio and a decreased or absent central pallor. Explanation: Hyperchromic RBCs have a decreased surface-to-volume ratio and a decreased or absent central pallor. True hyperchromia exists when the MCHC is 36%. 8. What is the characteristic of polychromatic RBCs? a) They have a central area of pallor greater than 3 µm b) They are gray-blue in color and usually larger than normal red cells c) They have less than the normal amount of hemoglobin d) They have a well hemoglobinized cytoplasm with a small but distinct zone of central pallor e) They have a decreased surface-to-volume ratio and a decreased or absent central pallor Answer: b) They are gray-blue in color and usually larger than normal red cells. Explanation: Polychromatic RBCs are gray-blue in color and usually larger than normal red cells. They are also known as reticulocytes and their count can be used as an indicator of bone marrow activity. 9. What is the RBC index that represents the average volume of RBCs? a) MCV b) MCH c) MCHC d) RDW e) Hct Answer: a) MCV. Explanation: MCV represents the average volume of RBCs and is calculated by dividing the hematocrit (Hct) by the RBC count and multiplying by 10. 10. What is the RBC index that represents the average weight of hemoglobin in RBCs? a) MCV b) MCH c) MCHC d) RDW e) Hct Answer: b) MCH. Explanation: MCH represents the average weight of hemoglobin in RBCs and is calculated by dividing the hemoglobin (Hb) by the RBC count and multiplying by 10. 1. What happens to glucose during anaerobic glycolysis? a) It is converted to pyruvate b) It is converted to lactic acid c) It is converted to acetyl-CoA d) It is converted to ATP e) It is converted to NADH Answer: b) It is converted to lactic acid. Explanation: During anaerobic glycolysis, glucose is broken down into lactic acid. 2. What is the function of the Hexose Monophosphate Shunt? a) Production of ATP b) Production of NADH c) Production of reduced glutathione to prevent denaturation of Hb d) Production of 2,3 DPG e) Production of pyruvate Answer: c) Production of reduced glutathione to prevent denaturation of Hb. Explanation: The Hexose Monophosphate Shunt is responsible for the production of reduced glutathione, which helps prevent denaturation of Hb. 3. What is the function of the Rapaport Leubering Pathway? a) Production of ATP b) Production of NADH c) Production of reduced glutathione to prevent denaturation of Hb d) Production of 2,3 DPG e) Production of pyruvate Answer: d) Production of 2,3 DPG. Explanation: The Rapaport Leubering Pathway is responsible for the production of 2,3 DPG, which regulates the affinity of the Hb molecule to O2. 4. What is the function of Methemoglobin Reductase? a) Production of ATP b) Production of NADH c) Maintenance of the iron present in HB molecule to its reduced state d) Production of 2,3 DPG e) Production of pyruvate Answer: c) Maintenance of the iron present in HB molecule to its reduced state. Explanation: Methemoglobin Reductase is responsible for maintaining the iron present in the Hb molecule to its reduced state. 5. What is the characteristic of a normochromic RBC? a) Central area of pallor of greater than 3 µm b) Gray-blue in color and usually larger than normal red cells c) Normal in color d) Decreased surface-to-volume ratio and a decreased or absent central pallor e) Has less than the normal amount of hemoglobin Answer: c) Normal in color. Explanation: A normochromic RBC is normal in color and has a well hemoglobinized cytoplasm with a small but distinct zone of central pallor. 6. What is the characteristic of a hyperchromic RBC? a) Central area of pallor of greater than 3 µm b) Gray-blue in color and usually larger than normal red cells c) Normal in color d) Decreased surface-to-volume ratio and a decreased or absent central pallor e) Has less than the normal amount of hemoglobin Answer: d) Decreased surface-to-volume ratio and a decreased or absent central pallor. Explanation: A hyperchromic RBC has a decreased surface-to-volume ratio and a decreased or absent central pallor. 7. What is the characteristic of a polychromatic RBC? a) Central area of pallor of greater than 3 µm b) Gray-blue in color and usually larger than normal red cells c) Normal in color d) Decreased surface-to-volume ratio and a decreased or absent central pallor e) Has less than the normal amount of hemoglobin Answer: b) Gray-blue in color and usually larger than normal red cells. Explanation: A polychromatic RBC is gray-blue in color and usually larger than normal red cells. 8. What is the RBC index that measures the average volume of RBC? a) MCV b) MCH c) MCHC d) Reticulocyte count e) Hematocrit Answer: a) MCV. Explanation: MCV measures the average volume of RBC and is calculated by dividing the hematocrit by the RBC count and multiplying by 10. 9. What is the RBC index that measures the average weight of Hb in RBC? a) MCV b) MCH c) MCHC d) Reticulocyte count e) Hematocrit Answer: b) MCH. Explanation: MCH measures the average weight of Hb in RBC and is calculated by dividing the Hb by the RBC count and multiplying by 10. 10. What is the normal range for MCV? a) 80-100 fl b) 26-34 pg c) 32-36 g/dL d) 0.5-1.5% e) 0.5-2.5% Answer: a) 80-100 fl. Explanation: The normal range for MCV is 80-100 fl. 1. What is the reference range for the average volume of RBC? a) 80-100 fl b) 100-120 fl c) 120-140 fl d) 140-160 fl e) 160-180 fl Answer: a) 80-100 fl. The average volume of RBC is measured by Hct/RBC x 10 and the reference range is 80-100 fl. 2. What is the reference range for the average weight of Hb in RBC? a) 10-20 pg b) 20-26 pg c) 26-32 pg d) 32-38 pg e) 38-44 pg Answer: c) 26-32 pg. The average weight of Hb in RBC is measured by Hb/RBC x 10 and the reference range is 26-32 pg. 3. What is the ratio of the weight of Hb to the volume of RBC? a) Hb/Hct x 10 b) Hct/RBC x 10 c) Hb/RBC x 100 d) RBC x 9 e) None of the above Answer: c) Hb/RBC x 100. The ratio of the weight of Hb to the volume of RBC is measured by Hb/Hct x 100 and the reference range is 32-36%. 4. Which condition is associated with Acanthocytes (Spur Cells)? a) Abetalipoproteinemia b) Vitamin E Deficiency c) Severe Liver Disease d) Splenectomy e) Malabsorption Answer: a) Abetalipoproteinemia. Acanthocytes (Spur Cells) are associated with Abetalipoproteinemia. 5. Which condition is associated with Codocytes (Target Cells)? a) Hemoglobinopathies (SS,CC, EE) b) Thalassemia c) Liver disease d) Postsplenectomy e) IDA Answer: a) Hemoglobinopathies (SS,CC, EE). Codocytes (Target Cells) are associated with Hemoglobinopathies (SS,CC, EE). 6. Which condition is associated with Spherocytes? a) Hereditary Spherocytosis b) Immune-mediated Hemolytic Anemia c) Hemolytic jaundice d) Transfused Cells e) Severe Burns Answer: a) Hereditary Spherocytosis. Spherocytes are associated with Hereditary Spherocytosis. 7. Which condition is associated with Drepanocytes (Sickle cells)? a) Sickle cell anemia b) SC disease c) G6PD Deficiency d) Myelofibrosis e) None of the above Answer: a) Sickle cell anemia. Drepanocytes (Sickle cells) are associated with Sickle cell anemia. 1. Which of the following conditions is characterized by the presence of sickle-shaped red blood cells? A. G6PD Deficiency B. Myelofibrosis with myeloid metaplasia C. Hemolytic uremic syndrome D. Sickle cell anemia E. Thrombotic thrombocytopenic purpura Answer: D. Sickle cell anemia Explanation: Sickle cell anemia is a genetic disorder that causes the production of abnormal hemoglobin, resulting in sickle-shaped red blood cells. 2. Which of the following conditions is characterized by the presence of teardrop-shaped red blood cells? A. Myelophthisic anemias B. Hemolytic uremic syndrome C. Pyropoikilocytosis D. Hereditary pyropoikilocytosis E. Thalassemia Answer: A. Myelophthisic anemias Explanation: Myelophthisic anemias are caused by the replacement of bone marrow with non-hematopoietic tissue, resulting in the production of abnormal red blood cells such as teardrop-shaped cells. 3. Which of the following conditions is characterized by the presence of schistocytes (fragmented red blood cells)? A. Iron deficiency anemia B. Infectious anemias C. Thalassemia D. Hemolytic uremic syndrome E. Newborn babies Answer: D. Hemolytic uremic syndrome Explanation: Hemolytic uremic syndrome is a condition characterized by the destruction of red blood cells, resulting in the production of fragmented red blood cells called schistocytes. 4. Which of the following types of anemia is caused by a decreased production of red blood cells? A. Relative anemia B. Iron deficiency anemia C. Hemolytic uremic syndrome D. Thalassemia E. None of the above Answer: D. Thalassemia Explanation: Thalassemia is a genetic disorder that causes a decreased production of red blood cells. 5. Which of the following types of anemia is caused by a defective heme synthesis? A. Iron deficiency anemia B. Thalassemia C. Hemolytic uremic syndrome D. G6PD Deficiency E. None of the above Answer: A. Iron deficiency anemia Explanation: Iron deficiency anemia is caused by a defective heme synthesis due to a lack of iron, which is necessary for the production of hemoglobin. bone marrow ■Causes: idiopathic, radiation, drugs, viruses, autoimmune disorders MULTIPLE CHOICE QUESTIONS: 1. What is the most common nutritional disorder that causes impaired or defective production of RBC? A. Vitamin C deficiency B. Iron deficiency anemia C. Vitamin B12 deficiency D. Folic acid deficiency E. Vitamin D deficiency Answer: B. Iron deficiency anemia. Iron is an essential component of hemoglobin, which is responsible for carrying oxygen in the blood. Iron deficiency leads to impaired hemoglobin production, resulting in microcytic hypochromic RBCs. 2. What is the laboratory finding in stage 3 of iron deficiency anemia? A. High serum iron, serum ferritin, and transferrin saturation B. Low serum iron, serum ferritin, and transferrin saturation C. High serum iron and serum ferritin, but low transferrin saturation D. Low serum iron and serum ferritin, but high transferrin saturation E. Normal serum iron, serum ferritin, and transferrin saturation Answer: B. Low serum iron, serum ferritin, and transferrin saturation. In stage 3 of iron deficiency anemia, there is a significant decrease in iron stores, resulting in impaired hemoglobin production and microcytic hypochromic RBCs. 3. What is the pathogenesis of megaloblastic anemia? A. Impaired DNA synthesis and delayed nucleus maturation B. Impaired heme synthesis and defective RBC production C. Impaired absorption of vitamin B12 D. Autoimmune disorder that attacks parietal cells E. Hematopoietic stem cell disorder characterized by pancytopenia Answer: A. Impaired DNA synthesis and delayed nucleus maturation. Megaloblastic anemia is caused by a deficiency of vitamin B12 or folic acid, which leads to impaired DNA synthesis and delayed nucleus maturation, resulting in larger-than-normal RBCs. 4. What is the clinical feature of pernicious anemia? A. Fatigue B. Breathlessness C. Pica D. Pagophagia E. Koilonychia Answer: B. Breathlessness. Pernicious anemia is caused by impaired absorption of vitamin B12, which is necessary for RBC production. The clinical features include fatigue, breathlessness, and neurological symptoms. 5. What is the characteristic feature of aplastic anemia? A. Microcytic hypochromic RBCs B. Larger-than-normal RBCs C. Pancytopenia D. High serum iron and transferrin saturation E. Low serum ferritin Answer: C. Pancytopenia. Aplastic anemia is a hematopoietic stem cell disorder characterized by pancytopenia, which is a decrease in all blood cell types. It is caused by various factors, including idiopathic, radiation, drugs, viruses, and autoimmune disorders. 1. Which disorder is characterized by pancytopenia and markedly hypocellular bone marrow? a) Hemolytic anemia b) G6PD deficiency c) Thalassemia d) Hereditary spherocytosis e) None of the above Answer: c) Thalassemia Explanation: Thalassemia is a hematopoietic stem cell disorder that is characterized by pancytopenia (anemia, neutropenia, and thrombocytopenia) with markedly hypocellular bone marrow (less than 30% cellularity). 2. Which laboratory finding is associated with G6PD deficiency? a) Increased reticulocyte count b) Decreased hemoglobin level c) Decreased MCV d) Decreased MCHC e) None of the above Answer: a) Increased reticulocyte count Explanation: G6PD deficiency is a red cell enzyme defect that is caused by a G6PD gene mutation. RBCs are susceptible to oxidative injury by free radicals, leading to hemolysis. The laboratory finding associated with G6PD deficiency is an increased reticulocyte count. 3. Which disorder is caused by a decrease in the synthesis of one or more globin chains? a) Hemolytic anemia b) G6PD deficiency c) Thalassemia d) Hereditary spherocytosis e) None of the above Answer: c) Thalassemia Explanation: Thalassemia is caused by a decrease in the synthesis of one or more globin chains. It is mostly seen in Mediterranean and Southeast Asian populations. The old name for b-thalassemias was Cooley's anemia. 4. Which laboratory finding is associated with hereditary spherocytosis? a) Decreased hemoglobin level b) Decreased MCV c) Decreased MCHC d) Increased reticulocyte count e) None of the above Answer: d) Increased reticulocyte count Explanation: Hereditary spherocytosis is a hemolytic anemia due to RBC membrane and enzyme defect. It is caused by a gene mutation in ANK1, SPTA1, SPTB, EPB42, or SLC4A1. The laboratory finding associated with hereditary spherocytosis is an increased reticulocyte count. 5. Which laboratory finding is associated with thalassemia? a) Increased MCV b) Increased MCHC c) Increased reticulocyte count d) Microcytic/hypochromic anemia with moderate number of target cells e) None of the above Answer: d) Microcytic/hypochromic anemia with moderate number of target cells Explanation: Thalassemia is characterized by a decrease in the synthesis of one or more globin chains. The laboratory finding associated with thalassemia is microcytic/hypochromic anemia with a moderate number of target cells. Other laboratory findings include nucleated RBCs, schistocytes, and spherocytes, as well as Howell-Jolly bodies, siderocytes, and Cabot rings. Diagnosis is confirmed when hemoglobin electrophoresis shows HbA2 increased over 2 percent and increased levels of HbF. 1. Which of the following are target cells seen in thalassemia? a) Neutrophils b) Eosinophils c) Nucleated RBCs d) Platelets e) Basophils Answer: c) Nucleated RBCs Explanation: Thalassemia is a group of inherited blood disorders that affect the production of hemoglobin. Target cells are seen in thalassemia and are characterized by abnormal shapes or sizes. Nucleated RBCs are one of the target cells seen in thalassemia. 2. Which of the following are clinical syndromes of b-thalassemia? a) b-thalassemia silent carrier b) b-thalassemia minor c) b-thalassemia major d) b-thalassemia intermedia e) All of the above Answer: e) All of the above Explanation: b-thalassemia has three clinical syndromes: b-thalassemia silent carrier, b-thalassemia minor, and b-thalassemia major. b-thalassemia intermedia is also a clinical syndrome of b-thalassemia. 3. Which of the following is a clinical syndrome of a-thalassemia? a) Silent carrier state b) a-thalassemia minor c) b-thalassemia major d) b-thalassemia intermedia e) None of the above Answer: b) a-thalassemia minor Explanation: a-thalassemia has two clinical syndromes: silent carrier state and a-thalassemia minor. Silent carrier state is caused by the deletion of one a-globin gene, leaving three functional a-globin genes. A-thalassemia minor is caused by the deletion of two a-globin genes. A) ■Contains 2 alpha and 2 beta globin chains ( α2β2). ■Functions in an oxygen-rich environment. ■Makes up about 97% of adult hemoglobin. HEMOGLOBIN VARIANTS 3.Adult Hemoglobin A2 (HbA2) ■Contains 2 alpha and 2 delta globin chains ( α2δ2). ■Makes up about 2-3% of adult hemoglobin. ■May increase in certain conditions such as beta-thalassemia trait. HEMOGLOBIN VARIANTS A. What is the major cause of HbH disease? 1. Deletion of three beta-globin genes 2. Deletion of three alpha-globin genes 3. Deletion of one alpha-globin gene 4. Deletion of one beta-globin gene 5. None of the above Answer: 2. Deletion of three alpha-globin genes Explanation: HbH disease is caused by the deletion of three alpha-globin genes, leaving only one alpha-globin gene to produce alpha chains. B. What is the composition of fetal hemoglobin (HbF)? 1. 2 alpha and 2 beta globin chains 2. 2 alpha and 2 delta globin chains 3. 2 alpha and 2 gamma globin chains 4. 2 beta and 2 delta globin chains 5. None of the above Answer: 3. 2 alpha and 2 gamma globin chains Explanation: Fetal hemoglobin (HbF) contains 2 alpha and 2 gamma globin chains (α2γ2) and functions in a reduced oxygen environment. C. What is the characteristic of homozygous a0-thalassemia? 1. Mild anemia 2. Absence of all alpha chain production 3. Deletion of three alpha-globin genes 4. Deletion of one alpha-globin gene 5. None of the above Answer: 2. Absence of all alpha chain production Explanation: Homozygous a0-thalassemia (––/––) results in the absence of all alpha chain production and usually results in death in utero or shortly after birth. 1. Which hemoglobin variant switches to hemoglobin A shortly before birth and is complete in 6 months? a) Adult Hemoglobin A (HbA) b) Adult Hemoglobin A2 (HbA2) c) Hemoglobin E (HbE) d) Hemoglobin C (HbC) e) Hemoglobin D (HbD) Answer: c) Hemoglobin E (HbE) Explanation: Hemoglobin E (HbE) is a hemoglobin variant that switches to hemoglobin A shortly before birth and is complete in 6 months. 2. What are the polypeptide chains in globin composed of in Adult Hemoglobin A (HbA)? a) Two alpha and two beta chains (α2β2) b) Two alpha and two delta chains (α2δ2) c) Two beta and two delta chains (β2δ2) d) Two gamma and two delta chains (γ2δ2) e) Two alpha and two gamma chains (α2γ2) Answer: a) Two alpha and two beta chains (α2β2) Explanation: Adult Hemoglobin A (HbA) is the major adult hemoglobin. The polypeptide chains in globin are composed of two alpha and two beta chains (α2β2). 3. What is the glycosylated fraction of Adult Hemoglobin A (HbA) that reflects sugar levels in the blood and is very sensitive in monitoring diabetics? a) HbA2 fraction b) HbE fraction c) HbC fraction d) HbD fraction e) A1C fraction Answer: e) A1C fraction Explanation: Adult Hemoglobin A (HbA) is subdivided into glycosylated fractions. A1C fraction reflects sugar levels in the blood and is very sensitive in monitoring diabetics. 4. What are the polypeptide chains in globin composed of in Adult Hemoglobin A2 (HbA2)? a) Two alpha and two beta chains (α2β2) b) Two alpha and two delta chains (α2δ2) c) Two beta and two delta chains (β2δ2) d) Two gamma and two delta chains (γ2δ2) e) Two alpha and two gamma chains (α2γ2) Answer: b) Two alpha and two delta chains (α2δ2) Explanation: Adult Hemoglobin A2 (HbA2) has polypeptide chains in globin that are composed of two alpha and two delta chains (α2δ2). 5. Which abnormal hemoglobin variant is the second commonest after sickle cell hemoglobin (HbS)? a) HbE b) HbC c) HbD d) HbS e) None of the above Answer: a) HbE Explanation: HbE is the second commonest abnormal hemoglobin after sickle cell hemoglobin (HbS). It results in a mild form of anemia and is an inherited homozygous trait found mostly in Asians. hoices: A) HbE is characterized by normochromic/normocytic anemia and spherocytes. B) HbC affects mostly blacks and generally produces no symptoms. C) HbD is caused by an amino acid substitution in the beta chain at position 121 of the glutamate with a glutamine amino acid. D) HbS is caused when valine replaces glutamic acid, and results in a decrease in hemoglobin solubility and function. E) None of the above. Answer: D) HbS is caused when valine replaces glutamic acid, and results in a decrease in hemoglobin solubility and function. Explanation: HbS is an abnormal hemoglobin variant caused by a genetic mutation that results in the substitution of valine for glutamic acid in the beta chain of hemoglobin. This leads to a decrease in hemoglobin solubility and function, causing the red blood cells to become sickle-shaped and leading to a variety of clinical symptoms. ious laboratory findings associated with sickle cell disease. Which of the following is NOT a common laboratory finding in sickle cell disease? a. Normochromic/normocytic anemia and polychromasia resulting from premature release of reticulocytes. b. Sickle cells, target cells, nucleated RBCs, and Howell-Jolly bodies in peripheral blood smear. c. Neutrophilia and increased platelets. d. Osmotic fragility test will be increased. e. All of the above are common laboratory findings in sickle cell disease. Answer: d. Osmotic fragility test will be increased. Explanation: The osmotic fragility test measures the ability of red blood cells to withstand changes in osmotic pressure. In sickle cell disease, the osmotic fragility test will be decreased due to the decreased solubility and function of hemoglobin. Therefore, option d is incorrect as it states that the osmotic fragility test will be increased. 1. What is the result of the osmotic fragility test in patients with abnormal hemoglobin variants? a. Increased fragility b. No change in fragility c. Decreased fragility d. Fragility cannot be determined e. Fragility varies depending on the variant Answer: c. Decreased fragility. This is because abnormal hemoglobin variants, such as HbS, cause red blood cells to become more rigid and less flexible, making them less able to withstand osmotic stress. 2. What are some screening tests for insoluble hemoglobins? a. Alkali denaturation and acid elution tests b. Hemoglobin solubility test and DNA analysis c. Hemoglobin electrophoresis and osmotic fragility test d. Complete blood count and reticulocyte count e. None of the above Answer: a. Alkali denaturation and acid elution tests are commonly used screening tests for insoluble hemoglobins. Other tests may also be used depending on the specific variant being screened for. 3. How is sickle cell anemia confirmed? a. Osmotic fragility test b. Hemoglobin solubility test c. Hemoglobin electrophoresis d. DNA analysis e. Complete blood count Answer: c. Hemoglobin electrophoresis is the definitive test for confirming sickle cell anemia. This test separates the different types of hemoglobin based on their charge, allowing for the identification of abnormal variants such as HbS. 4. What is the result of the hemoglobin solubility test in patients with HbS? a. Clear solution b. Turbid solution c. No change in solution clarity d. Solution color changes e. Solution viscosity changes Answer: b. Turbid solution. HbS is insoluble in its deoxygenated state, causing the solution to become turbid when the reducing agent and lysing agent are added to the blood sample. 5. How does hemoglobin electrophoresis separate hemoglobin molecules? a. Based on their size b. Based on their shape c. Based on their oxygen affinity d. Based on their total molecular charge e. Based on their amino acid sequence Answer: d. Hemoglobin electrophoresis separates hemoglobin molecules based on their total molecular charge. This allows for the identification of different hemoglobin variants based on their unique charge characteristics.