Lec.2 histo.pdf

 RBCs & Erythropoiesis Component of the blood and Preparing a blood smear 1. What is the fluid extracellular material in which blood cells are suspended?  A) Serum  B) Plasma  C) Lymph  D) Interstitial fluid Answer: B) Plasma 2. Which of the follo...

 RBCs & Erythropoiesis Component of the blood and Preparing a blood smear 1. What is the fluid extracellular material in which blood cells are suspended?  A) Serum  B) Plasma  C) Lymph  D) Interstitial fluid Answer: B) Plasma 2. Which of the following is not considered a “formed element” in blood?  A) Red blood cells  B) White blood cells  C) Platelets  D) Plasma proteins Answer: D) Plasma proteins 3. What is the purpose of using stains like Leishman’s stain in blood smear preparation?  A) To identify blood glucose levels  B) To make blood cells visible under the microscope  C) To increase the volume of blood in the sample  D) To detect blood pressure changes Answer: B) To make blood cells visible under the microscope 4. What type of dyes are present in Leishman’s stain?  A) Acidic and neutral  B) Acidic and basic  C) Basic and neutral  D) Only polychromatic dyes Answer: B) Acidic and basic ① 5. Which of the following stains is considered a “neutral stain” used in blood smears?  A) Giemsa stain  B) Leishman’s stain  C) Wright stain  D) Hematoxylin Answer: B) Leishman’s stain 6. Which of the following is an example of a Romanowsky stain?  A) Leishman’s stain  B) Giemsa stain  C) Eosin stain  D) Crystal violet Answer: B) Giemsa stain 7. What is the function of eosin in Leishman’s stain?  A) It stains acidic components of the cell  B) It stains basic components of the cell  C) It stains lipids in the cell membrane  D) It enhances the color of plasma proteins Answer: A) It stains acidic components of the cell 8. Which staining technique uses polychromatic dyes for blood smear preparation?  A) Neutral staining  B) Simple staining  C) Romanowsky staining  D) Negative staining Answer: C) Romanowsky staining shape of RBCs 9. What is the primary advantage of the biconcave shape of RBCs?  A) It increases oxygen-carrying capacity  B) It facilitates gas exchange by increasing surface area  C) It makes the RBCs more flexible  D) It allows RBCs to store more hemoglobin Answer: B) It facilitates gas exchange by increasing surface area ② 10. How are RBCs viewed using Transmission Electron Microscopy (TEM) inside capillaries?  A) Biconcave  B) Spherical  C) Dumbbell-shaped  D) Disc-shaped Answer: C) Dumbbell-shaped 11. What happens to RBCs in sickle cell disease?  A) They are more flexible and have a longer lifespan  B) They become less flexible and more fragile, causing anemia  C) They are more resistant to hemolysis  D) They increase in size and flexibility Answer: B) They become less flexible and more fragile, causing anemia 12. What is the normal diameter range of RBCs?  A) 5-7 µm  B) 7-10 µm  C) 6-9 µm  D) 10-12 µm Answer: C) 6-9 µm 13. In macrocytic anemia, what is the typical size of RBCs?  A) Greater than 6 µm  B) Less than 6 µm  C) Greater than 9 µm  D) Between 7-8 µm Answer: C) Greater than 9 µm 14. What is the average thickness of RBCs at the center?  A) 2.6 µm  B) 1.5 µm  C) 0.75 µm  D) 3.0 µm Answer: C) 0.75 µm ③ 15. What is the normal RBC concentration in males?  A) 3.9-5.5 million/µL  B) 4.1-6.0 million/µL  C) 5.5-7.0 million/µL  D) 3.5-5.0 million/µL Answer: B) 4.1-6.0 million/µL Structure of RBCs 16. Which component forms the largest percentage of the RBC membrane?  A) Proteins  B) Carbohydrates  C) Phospholipids  D) Cholesterol Answer: A) Proteins 17. Which protein network supports the RBC membrane and provides its flexibility?  A) Myosin and tropomyosin  B) Spectrin, ankyrin, and actin  C) Keratin and collagen  D) Tubulin and actin Answer: B) Spectrin, ankyrin, and actin 18. What is the primary function of the flexibility provided by the RBC cytoskeleton?  A) To enable oxygen transport  B) To increase hemoglobin binding  C) To allow easy passage through small capillaries  D) To facilitate nutrient absorption Answer: C) To allow easy passage through small capillaries 19. Where are the ABO blood group antigens located on the RBC membrane?  A) Embedded within the lipid bilayer  B) On the cytoskeleton  C) Formed of outer carbohydrates and protein molecules  D) Attached to hemoglobin molecules Answer: C) Formed of outer carbohydrates and protein molecules ④ 20. What cellular organelles are absent in mature RBCs?  A) Nucleus and mitochondria  B) Ribosomes and rough ER  C) Golgi apparatus and lysosomes  D) All of the above Answer: D) All of the above 21. Which molecule densely fills RBCs and is essential for oxygen transport?  A) Hemoglobin  B) Spectrin  C) Albumin  D) Myoglobin Answer: A) Hemoglobin 22. What is the primary source of energy for RBCs?  A) Oxidative phosphorylation  B) Anaerobic glycolysis  C) Beta-oxidation  D) Gluconeogenesis Answer: B) Anaerobic glycolysis 23. What is the lifespan of a typical RBC?  A) 60 days  B) 90 days  C) 120 days  D) 150 days Answer: C) 120 days 24. Where are dead or worn-out RBCs removed from circulation?  A) Lungs and heart  B) Spleen, liver, and bone marrow  C) Kidneys and liver  D) Lymph nodes and thymus Answer: B) Spleen, liver, and bone marrow ⑤ 25. What is the major function of RBCs in the body?  A) Nutrient absorption  B) Defense against pathogens  C) Oxygen and carbon dioxide transport  D) Hormone regulation Answer: C) Oxygen and carbon dioxide transport Hemopoiesis 26. What is the process of blood cell production called?  A) Hemolysis  B) Hemostasis  C) Hemoglobin synthesis  D) Hemopoiesis Answer: D) Hemopoiesis 27. In adults, where does the majority of blood cell production take place?  A) Liver  B) Spleen  C) Bone marrow  D) Lymph nodes Answer: C) Bone marrow 28. During fetal development, where does blood cell production initially occur?  A) Yolk sac  B) Liver  C) Spleen  D) Bone marrow Answer: A) Yolk sac 29. All blood cells are derived from which type of stem cell?  A) Multipotent hematopoietic stem cells  B) Pluripotent hematopoietic stem cells  C) Oligopotent hematopoietic stem cells  D) Unipotent hematopoietic stem cells Answer: B) Pluripotent hematopoietic stem cells ⑥ 30. What are progenitor cells committed to producing?  A) All types of tissue cells  B) Specific types of blood cells  C) Only red blood cells  D) Only platelets Answer: B) Specific types of blood cells 31. Which progenitor cells give rise to neutrophils, eosinophils, basophils, and monocytes?  A) Colony forming unit Lymphocytes (CFU-L)  B) Colony forming unit Erythrocytes (CFU-E)  C) Colony forming unit Granulocytes-monocytes (CFU-GM)  D) Colony forming unit Megakaryocytes (CFU-Meg) Answer: C) Colony forming unit Granulocytes-monocytes (CFU-GM) 32. Which blood cell type arises from Colony Forming Unit Erythrocytes (CFU-E)?  A) Platelets  B) Red blood cells (erythrocytes)  C) B-lymphocytes  D) Monocytes Answer: B) Red blood cells (erythrocytes) 33. Which progenitor cell is responsible for the production of platelets?  A) CFU-GM  B) CFU-Meg  C) CFU-L  D) CFU-E Answer: B) CFU-Meg 34. Which of the following is a characteristic of hemopoietic stem cells (HSC)?  A) They only differentiate and do not self-renew  B) They produce all types of tissue cells  C) They are capable of self-renewal and differentiation into progenitors  D) They only produce lymphoid cells Answer: C) They are capable of self-renewal and differentiation into progenitors ⑦ 35. Natural killer cells originate from which progenitor cell type?  A) Myeloid stem cells  B) CFU-Lymphocytes (CFU-L)  C) CFU-Erythrocytes  D) CFU-Megakaryocytes Answer: B) CFU-Lymphocytes (CFU-L) 36. Which stage of erythropoiesis is characterized by the extrusion of the nucleus?  A) Proerythroblast  B) Basophilic erythroblast  C) Polychromatophilic erythroblast  D) Reticulocyte Answer: D) Reticulocyte 37. In which stage of erythropoiesis does the cell become basophilic and acidophilic?  A) Proerythroblast  B) Basophilic erythroblast  C) Polychromatophilic erythroblast  D) Orthochromatophilic erythroblast Answer: C) Polychromatophilic erythroblast 38. Which stage of erythropoiesis has a nucleus that is condensed and eccentric?  A) Proerythroblast  B) Basophilic erythroblast  C) Polychromatophilic erythroblast  D) Orthochromatophilic erythroblast Answer: D) Orthochromatophilic erythroblast 39. The cytoplasm of a reticulocyte is characterized by:  A) Basophilia  B) Acidophilia  C) A reticulum of ribosomal RNA  D) Both B and C Answer: D) Both B and C ⑧ 40. Which stage of erythropoiesis immediately precedes the mature erythrocyte?  A) Proerythroblast  B) Basophilic erythroblast  C) Polychromatophilic erythroblast  D) Reticulocyte Answer: D) Reticulocyte 41. In which stage of erythropoiesis does the nucleus become less active?  A) Proerythroblast  B) Basophilic erythroblast  C) Polychromatophilic erythroblast  D) Orthochromatophilic erythroblast Answer: B) Basophilic erythroblast 42. The cytoplasm of a proerythroblast is:  A) Basophilic  B) Acidophilic  C) Neutral  D) Polychromatophilic Answer: A) Basophilic 43. What is the first precursor (blast) cell of red blood cells (RBCs)?  A) Proerythroblast  B) Erythrocyte  C) Reticulocyte  D) Megakaryoblast Answer: A) Proerythroblast 44. Which of the following is true about reticulocytes?  A) They make up 10% of total RBCs  B) They are fully mature RBCs  C) They contain mitochondria and ribosomal RNA  D) They are the final stage of RBC maturation Answer: C) They contain mitochondria and ribosomal RNA ⑨ 45. What does a rise in reticulocytes in the peripheral blood indicate?  A) A decrease in RBC production  B) An increase in erythrocyte production following hemorrhage or hemolysis  C) A failure of the bone marrow  D) A decrease in hemoglobin concentration Answer: B) An increase in erythrocyte production following hemorrhage or hemolysis 46. Which of the following is the immediate precursor to reticulocytes in erythropoiesis?  A) Megakaryocyte  B) Proerythroblast  C) Erythroblast  D) Normoblast Answer: D) Normoblast 47. In normal peripheral blood, what percentage of RBCs are reticulocytes?  A) 1%  B) 5%  C) 10%  D) 15% Answer: A) 1% 48. Which condition would most likely lead to reticulocytosis?  A) Anemia due to chronic blood loss  B) Vitamin deficiency anemia  C) Severe erythrocyte loss after hemorrhage  D) Iron overload Answer: C) Severe erythrocyte loss after hemorrhage 49. What cellular structure helps identify reticulocytes under a microscope?  A) Nucleus  B) Ribosomal RNA  C) Hemoglobin content  D) Golgi apparatus Answer: B) Ribosomal RNA ⑩ 50. Which of the following best describes reticulocytosis?  A) Increased reticulocyte count in response to erythrocyte destruction or blood loss  B) Decreased RBC production leading to fewer reticulocytes in the blood  C) Increased mature RBCs with decreased reticulocytes  D) Decreased RBC count without an increase in reticulocytes Answer: A) Increased reticulocyte count in response to erythrocyte destruction or blood loss ⑪