- رُكْـنُ الْجَامِعَـةِ

B) Progesterone C) Human chorionic gonadotropin (hCG) D) Human placental lactogen (hPL) Answer: C --- 49. The fetal surface of the placenta is: A) Rough and divided into cotyledons B) Smooth and covered by amnion C) Attached directly to the myometrium D) Composed only of cytotrophoblast Answer: B --- 50. The umbilical cord contains: A) Two umbilical veins and one artery B) One umbilical vein and two arteries C) One umbilical vein and one artery D) Two veins and two arteries Answer: B --- 51. The gelatinous substance surrounding the umbilical cord vessels is called: A) Wharton's jelly B) Heuser's membrane C) Amniotic fluid D) Decidua basalis Answer: A --- 52. In limb development, hyaline cartilage forms and digital rays appear in the hand during week: A) 4 B) 5 C) 6 D) 7 Answer: C --- 53. Endochondral ossification in limb development begins during week: A) 5 B) 6 C) 7 D) 8 Answer: C --- 54. The great toe and thumb rotate in opposite directions by week: A) 6 B) 7 C) 8 D) 9 Answer: C --- 55. Meromelia is defined as: A) Complete absence of a limb B) Partial absence of a limb C) Fusion of digits D) Reduction in digit length Answer: B --- 56. Brachydactyly refers to: A) Absent digits B) Webbed digits C) Extra digits D) Shortened digits Answer: D --- 57. During week 5 of development, which of the following occurs? A) Neural tube closes completely B) Rapid growth of the head and brain C) Formation of digital rays in foot D) Ossification begins Answer: B --- 58. The chorionic plate is formed by: A) Cytotrophoblast only B) Syncytiotrophoblast only C) Extraembryonic mesoderm lining the inside of the cytotrophoblast D) Hypoblast cells Answer: C --- 59. The only place where extraembryonic mesoderm traverses the chorionic cavity is the: A) Amniotic membrane B) Connecting stalk C) Yolk sac D) Neural plate Answer: B --- 60. By the end of the embryonic period, the main organ systems have been established and the embryo has recognizable external features. This occurs by the end of the: A) 1st month B) 2nd month C) 3rd month D) 4th month Answer: B

D) Amniotic membrane Answer: A --- 23. Fusion of the neural folds to form the neural tube begins in which region? A) Cranial region B) Caudal region C) Cervical region D) Thoracic region Answer: C --- 24. Endoderm gives rise to all of the following EXCEPT: A) Epithelial lining of the respiratory tract B) Liver C) Pancreas D) Dermis of skin Answer: D (Dermis is derived from mesoderm) --- 25. Mesoderm gives rise to: A) Hair and nails B) Brain and spinal cord C) Muscles and bones D) Thyroid gland Answer: C --- 26. Ectoderm gives rise to: A) Kidneys and reproductive organs B) Blood vessels and heart C) Nervous system and epidermis D) Lining of the digestive tract Answer: C --- 27. During the third week, the embryo establishes all the following axes EXCEPT: A) Cranial-caudal B) Dorsal-ventral C) Left-right D) Proximal-distal Answer: D --- 28. The embryonic period (organogenesis) extends from: A) Day 1 to week 2 B) Week 2 to week 4 C) Week 3 to week 8 D) Week 9 to birth Answer: C --- 29. By the end of the embryonic period (8 weeks): A) The fetus is viable outside the womb B) All major organ systems have been established C) The embryo is about 30 cm long D) Limb buds first appear Answer: B --- 30. During week 4, the heart begins beating at approximately day: A) 15 B) 18 C) 22 D) 28 Answer: C --- 31. During week 4, the embryo begins body folding and becomes: A) Straight B) C-shaped C) S-shaped D) Completely flat Answer: B --- 32. Digital rays (future fingers) form during which week? A) Week 4 B) Week 5 C) Week 6 D) Week 8 Answer: C --- 33. Ossification of bones begins and the tail begins to regress during: A) Week 5 B) Week 6 C) Week 7 D) Week 8 Answer: C --- 34. By the end of week 8, the embryo measures approximately: A) 10 mm B) 20 mm C) 30 mm D) 50 mm Answer: C --- 35. The transition from embryo to fetus occurs at: A) End of week 4 B) End of week 6 C) End of week 8 D) End of week 12 Answer: C --- 36. Amelia is a clinical condition defined as: A) Webbed digits B) Extra digits C) Absent limb D) Partially absent limb Answer: C --- 37. Syndactyly refers to: A) Shortened digits B) Webbed digits C) Absent digits D) Extra digits Answer: B --- 38. Polydactyly is the presence of: A) Webbed fingers B) Shortened fingers C) Extra digits D) Missing limb Answer: C --- 39. The fetal period begins at the: A) 8th week B) 9th week (third month) C) 12th week D) 16th week Answer: B --- 40. During the third month of fetal development, the face becomes more human-like and the eyes move to the: A) Sides of the head B) Top of the head C) Front of the face D) Back of the head Answer: C --- 41. At the end of the third month, the fetus weighs approximately: A) 15 g B) 45 g C) 200 g D) 600 g Answer: B --- 42. At the end of the third month, the fetal length is approximately: A) 3-4 cm B) 7-9 cm C) 15-20 cm D) 30 cm Answer: B --- 43. During the fourth to sixth months, the fetus grows rapidly and the mother may feel fetal movements called: A) Quickening B) Implantation C) Gastrulation D) Neurulation Answer: A (Inferred from content; standard knowledge) --- 44. At the end of the sixth month, the fetus may survive if born prematurely, but survival is difficult. Its approximate weight is: A) 200 g B) 600 g C) 1500 g D) 3000 g Answer: B --- 45. During the seventh month to birth, rapid weight gain occurs due to: A) Muscle hypertrophy B) Bone elongation C) Subcutaneous fat deposition D) Increased amniotic fluid Answer: C --- 46. At birth, the average weight of a full-term newborn is approximately: A) 1500-2000 g B) 2000-2500 g C) 2500-2800 g D) 3000-3400 g Answer: D --- 47. The placenta is a temporary organ that connects mother and fetus. All are functions of the placenta EXCEPT: A) Gas exchange B) Nutrient transfer C) Fetal hormone production (e.g., testosterone) D) Waste removal Answer: C (Placenta produces hCG, progesterone, estrogen, hPL – not primarily fetal sex hormones) --- 48. Which hormone produced by the placenta maintains the corpus luteum in early pregnancy? A) Estrogen

1. The second week of development is often called the "week of twos" because of the formation of all the following pairs EXCEPT: A) Cytotrophoblast and syncytiotrophoblast B) Epiblast and hypoblast C) Somatopleuric and splanchnopleuric mesoderm D) Neural crest and neural tube Answer: D (Neural crest and neural tube form during the third week, not the second) --- 2. During the second week, the embryoblast differentiates into which two layers? A) Cytotrophoblast and syncytiotrophoblast B) Epiblast and hypoblast C) Somatopleure and splanchnopleure D) Ectoderm and endoderm Answer: B --- 3. Which structure forms from the hypoblast and together they create the primitive yolk sac? A) Exocoelomic (Heuser's) membrane B) Amniotic membrane C) Chorionic membrane D) Connecting stalk Answer: A --- 4. At day 9, vacuoles form within the syncytium and fuse to create spaces called: A) Sinusoids B) Lacunae C) Villi D) Coeloms Answer: B --- 5. The uteroplacental circulation is established when lacunae connect with: A) Amniotic cavity B) Maternal sinusoids (capillaries) C) Yolk sac cavity D) Exocoelomic cyst Answer: B --- 6. Extraembryonic mesoderm derived from the yolk sac forms large cavities that later fuse to create the: A) Amniotic cavity B) Primitive yolk sac C) Extraembryonic coelom (chorionic cavity) D) Neural tube Answer: C --- 7. The connecting stalk later develops into which structure? A) Notochord B) Umbilical cord C) Neural tube D) Yolk sac Answer: B --- 8. Which statement about the bilaminar germ disc is correct? A) It grows very rapidly during the second week B) It remains very small (0.1-0.2 mm) during the second week C) It forms the neural plate by day 14 D) It is composed of ectoderm and mesoderm Answer: B --- 9. Bleeding at the implantation site around the 28th day of development may be confused with: A) Ovulation pain B) Menstrual bleeding C) Rupture of the amniotic sac D) Placental abruption Answer: B --- 10. Primary villi of the trophoblast consist of: A) Syncytium only B) Cytotrophoblast only C) Cellular column of cytotrophoblast surrounded by syncytium D) Extraembryonic mesoderm core Answer: C --- 11. The most characteristic event of the third week of development is: A) Implantation B) Gastrulation C) Formation of the placenta D) Folding of the embryo Answer: B --- 12. Gastrulation establishes the three germ layers: ectoderm, mesoderm, and endoderm. These derive from which original cell population? A) Hypoblast B) Cytotrophoblast C) Epiblast D) Syncytiotrophoblast Answer: C --- 13. The primitive streak first becomes clearly visible as a narrow groove on day: A) 9-10 B) 11-12 C) 15-16 D) 21-22 Answer: C --- 14. The cephalic end of the primitive streak, which contains the primitive pit, is called the: A) Prechordal plate B) Cloacal membrane C) Primitive node (Hensen's node) D) Neural crest Answer: C --- 15. During gastrulation, epiblast cells that displace the hypoblast will form: A) Ectoderm B) Mesoderm C) Endoderm D) Notochord Answer: C --- 16. Cells from the epiblast that migrate between the epiblast and the newly created endoderm will form: A) Ectoderm B) Mesoderm C) Endoderm D) Amnion Answer: B --- 17. The remaining epiblast cells after gastrulation form: A) Endoderm B) Mesoderm C) Ectoderm D) Yolk sac Answer: C --- 18. The notochord is derived from: A) Ectoderm B) Endoderm C) Mesoderm D) Trophoblast Answer: C --- 19. Which of the following is a function of the notochord? A) Formation of blood cells B) Inducing neural tube formation C) Producing amniotic fluid D) Forming the placenta Answer: B --- 20. The notochord establishes the primitive axis of the embryo and contributes to the development of the: A) Limb buds B) Heart C) Vertebral column D) Liver Answer: C --- 21. The process by which the neural plate forms the neural tube is called: A) Gastrulation B) Neurulation C) Organogenesis D) Implantation Answer: B --- 22. Induction of the neural plate is carried out by the underlying notochord and: A) Prechordal mesoderm B) Hypoblast C) Cytotrophoblast

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At birth, a female has approximately how many oocytes? · A) 400,000 · B) 1-2 million · C) 400 · D) 10,000 Answer: B) 1-2 million --- 46. Which of the following correctly describes the chromosome number in a secondary oocyte before fertilization? · A) Diploid (2n) · B) Haploid (n) · C) Tetraploid (4n) · D) 46 chromosomes Answer: B) Haploid (n) --- 47. The zona pellucida degenerates to allow: · A) Fertilization · B) Cleavage · C) Implantation · D) Ovulation Answer: C) Implantation --- 48. Testosterone promotes which process during spermatogenesis? · A) Mitosis of spermatogonia · B) Meiosis and sperm maturation · C) Formation of polar bodies · D) Degeneration of excess cytoplasm Answer: B) Meiosis and sperm maturation --- 49. Which statement about oogenesis is true? · A) Oogonia divide by meiosis during fetal life · B) Primary oocytes are arrested at Metaphase II until puberty · C) One primary oocyte produces four functional ova · D) Oogenesis is a cyclical process tied to the menstrual cycle Answer: D) Oogenesis is a cyclical process tied to the menstrual cycle --- 50. The entire process from spermatogonia to mature spermatozoa takes approximately: · A) 24 hours · B) 7 days · C) 74 days · D) 90 days Answer: C) 74 days

Answer: D) Acrosome --- 21. Where do spermatozoa obtain full maturity? · A) Seminiferous tubules · B) Vas deferens · C) Epididymis · D) Rete testis Answer: C) Epididymis --- 22. How many spermatozoa are produced daily on average? · A) 30 million · B) 100 million · C) 300 million · D) 500 million Answer: C) 300 million --- 23. Oogenesis occurs in which location? · A) Fallopian tubes · B) Uterus · C) Ovaries · D) Vagina Answer: C) Ovaries --- 24. When does oogenesis begin? · A) At puberty · B) During fetal life · C) At birth · D) At menopause Answer: B) During fetal life --- 25. At what stage do primary oocytes arrest until puberty? · A) Metaphase II · B) Prophase I · C) Anaphase I · D) Telophase II Answer: B) Prophase I --- 26. How many oocytes are typically ovulated during a female's reproductive life? · A) ~1-2 million · B) ~400,000 · C) ~400 · D) ~1,000 Answer: C) ~400 --- 27. Which hormone triggers ovulation? · A) FSH · B) GnRH · C) Estrogen · D) LH Answer: D) LH --- 28. Meiosis I in oogenesis is completed: · A) At fertilization · B) During fetal life · C) Just before ovulation · D) After implantation Answer: C) Just before ovulation --- 29. The first polar body is produced after: · A) Meiosis II · B) Completion of fertilization · C) Meiosis I · D) Mitosis of oogonia Answer: C) Meiosis I --- 30. Meiosis II in oogenesis is completed only if: · A) Puberty occurs · B) Fertilization occurs · C) The follicle ruptures · D) Progesterone levels rise Answer: B) Fertilization occurs --- 31. One primary oocyte ultimately produces: · A) Four functional ova · B) One ovum + three polar bodies · C) Two ova + two polar bodies · D) Four polar bodies Answer: B) One ovum + three polar bodies --- 32. Polar bodies are: · A) Large, functional cells · B) Small, non-functional cells that degenerate · C) Precursors to sperm · D) Cells that form the placenta Answer: B) Small, non-functional cells that degenerate --- 33. Ovulation typically occurs on which day of the menstrual cycle? · A) Day 1 · B) Day 7 · C) Day 14 · D) Day 28 Answer: C) Day 14 --- 34. Fertilization usually occurs in which part of the fallopian tube? · A) Infundibulum · B) Ampulla · C) Isthmus · D) Interstitial segment Answer: B) Ampulla --- 35. The product of fertilization is called a: · A) Morula · B) Blastocyst · C) Zygote · D) Gamete Answer: C) Zygote --- 36. Cleavage refers to: · A) Growth of the embryo · B) Rapid mitotic divisions without growth · C) Implantation into the uterus · D) Formation of the acrosome Answer: B) Rapid mitotic divisions without growth --- 37. The solid ball of 16-32 cells formed by day 3 is called: · A) Blastocyst · B) Morula · C) Trophoblast · D) Inner cell mass Answer: B) Morula --- 38. By day 4, compaction results in two cell populations. The outer cells become the: · A) Inner cell mass · B) Embryo proper · C) Trophoblast · D) Blastocoel Answer: C) Trophoblast --- 39. The inner cell mass of the blastocyst will form: · A) The placenta only · B) The future embryo · C) The yolk sac only · D) The zona pellucida Answer: B) The future embryo --- 40. The fluid-filled cavity inside the blastocyst is called: · A) Blastocoel · B) Amniotic cavity · C) Yolk sac · D) Chorionic cavity Answer: A) Blastocoel --- 41. What is "hatching" in embryonic development? · A) The blastocyst attaching to the uterine wall · B) The blastocyst degenerating the zona pellucida to emerge · C) The morula forming a cavity · D) The sperm penetrating the ovum Answer: B) The blastocyst degenerating the zona pellucida to emerge --- 42. By which day does hatching typically occur? · A) Day 3 · B) Day 4 · C) Day 5 · D) Day 6 Answer: D) Day 6 --- 43. Which cells provide nourishment and support during spermatogenesis? · A) Leydig cells · B) Sertoli cells · C) Spermatocytes · D) Interstitial cells Answer: B) Sertoli cells --- 44. The midpiece of a mature sperm contains many: · A) Enzymes · B) Mitochondria · C) Nuclei · D) Acrosomes Answer: B) Mitochondria --- 45.

1. What does the term "embryology" literally mean? · A) The study of fetuses · B) The study of embryos · C) The study of gametes · D) The study of chromosomes Answer: B) The study of embryos --- 2. According to the lecture, prenatal development is described as: · A) A process from a single cell to a baby in 9 months · B) A process from fertilization to birth only · C) A process that begins at puberty · D) A process that excludes fetal development Answer: A) A process from a single cell to a baby in 9 months --- 3. Which of the following is a practical value of studying embryology? · A) Understanding only abnormal structures · B) Helping to understand causes of variations in human structure · C) Replacing the need for gross anatomy · D) Focusing solely on infertility treatments Answer: B) Helping to understand causes of variations in human structure --- 4. Birth defects are a leading cause of: · A) Adult disability · B) Infant mortality · C) Genetic mutations only · D) Infertility Answer: B) Infant mortality --- 5. Gametogenesis is the conversion of germ cells into: · A) Somatic cells · B) Zygotes · C) Male and female gametes · D) Epiblast cells Answer: C) Male and female gametes --- 6. Primordial germ cells (PGCs) are first found in the: · A) Yolk sac (after migration) · B) Developing gonads · C) Epiblast (2nd week) · D) Testes Answer: C) Epiblast (2nd week) --- 7. By which week do PGCs arrive at the developing gonads? · A) 3rd week · B) 4th week · C) End of 5th week · D) 6th week Answer: C) End of 5th week --- 8. Gametogenesis includes which two processes? · A) Mitosis and apoptosis · B) Meiosis and cytodifferentiation · C) Fertilization and cleavage · D) Implantation and gastrulation Answer: B) Meiosis and cytodifferentiation --- 9. In humans, how many chromosomes are present in a diploid somatic cell? · A) 23 · B) 46 · C) 48 · D) 44 Answer: B) 46 --- 10. What is a haploid cell? · A) A cell with 46 chromosomes · B) A cell with two sets of DNA · C) A cell with 23 chromosomes · D) A replicating somatic cell Answer: C) A cell with 23 chromosomes --- 11. The 23 pairs of human chromosomes consist of: · A) 22 autosomes + 1 sex chromosome · B) 22 matching autosomes + 2 sex chromosomes · C) 23 autosomes only · D) 22 sex chromosomes + 1 autosome Answer: B) 22 matching autosomes + 2 sex chromosomes --- 12. Spermatogenesis occurs in which specific location? · A) Epididymis · B) Seminiferous tubules of the testes · C) Vas deferens · D) Prostate gland Answer: B) Seminiferous tubules of the testes --- 13. Which cells produce testosterone essential for spermatogenesis? · A) Sertoli cells · B) Spermatogonia · C) Leydig cells · D) Primary spermatocytes Answer: C) Leydig cells --- 14. When does spermatogenesis begin in males? · A) During fetal life · B) At birth · C) At puberty · D) At age 25 Answer: C) At puberty --- 15. In the HPG axis, GnRH is secreted by the: · A) Pituitary gland · B) Hypothalamus · C) Testes · D) Adrenal gland Answer: B) Hypothalamus --- 16. FSH from the pituitary stimulates spermatogenesis via which cells? · A) Leydig cells · B) Germ cells · C) Sertoli cells · D) Spermatids Answer: C) Sertoli cells --- 17. The spermatogonial phase involves: · A) Meiosis only · B) Mitotic division of spermatogonia · C) Formation of the acrosome · D) Maturation into spermatozoa Answer: B) Mitotic division of spermatogonia --- 18. Meiosis I in spermatogenesis converts a primary spermatocyte into: · A) Two secondary spermatocytes (n) · B) Four spermatids · C) Two spermatogonia · D) One secondary spermatocyte and one polar body Answer: A) Two secondary spermatocytes (n) --- 19. The process of spermiogenesis involves: · A) Reduction of chromosome number · B) Mitotic division of spermatogonia · C) Maturation of spermatids into spermatozoa · D) Formation of secondary spermatocytes Answer: C) Maturation of spermatids into spermatozoa --- 20. Which structure of mature sperm contains enzymes to penetrate the ovum? · A) Nucleus · B) Midpiece · C) Tail · D) Acrosome

A) Too many differentiation pathways B) Delivery to target organ C) Absence of ethical issues D) Perfect immune tolerance Answer: B) Delivery to target organ --- 47. High dose of CD34⁺ cells (>8 × 10⁶/kg) results in: A) Slower engraftment B) Faster engraftment C) Higher graft failure D) More GVHD only Answer: B) Faster engraftment --- 48. MSC therapy is mostly supportive rather than curative because: A) They are highly immunogenic B) Limited differentiation potential C) They cause teratomas D) They cannot secrete growth factors Answer: B) Limited differentiation potential --- 49. One mechanism of immune evasion for stem cells is: A) Increasing MHC expression B) Encapsulating cells in biomaterials C) Stopping all cell division D) Using larger needles Answer: B) Encapsulating cells in biomaterials --- 50. Long‑term risk of stem cell therapy includes: A) Immediate cure B) No follow‑up needed C) Unknown effects in some tissues D) Guaranteed immune tolerance Answer: C) Unknown effects in some tissues

Answer: B) Donor immune cells attacking recipient’s tissues --- 22. Symptoms of GVHD include all except: A) Skin rash B) Liver dysfunction C) Gut inflammation D) Increased platelet production Answer: D) Increased platelet production --- 23. Graft failure after transplant is most likely due to: A) High stem cell dose B) Poor stem cell quality or immune rejection C) Too many CD34⁺ cells D) Syngeneic donor Answer: B) Poor stem cell quality or immune rejection --- 24. Organ toxicity in transplant patients is mainly caused by: A) Stem cell infusion B) Pre‑transplant conditioning (chemo/radiation) C) GVHD D) Immunosuppression only Answer: B) Pre‑transplant conditioning (chemo/radiation) --- 25. Which cells are considered immune‑privileged due to immunosuppressive secretion? A) HSC B) ESC C) MSC D) iPSC Answer: C) MSC --- 26. T‑cell mediated rejection of transplanted stem cells involves: A) Antibodies attacking stem cells B) Cytotoxic T cells attacking transplanted cells C) NK cells only D) Macrophages only Answer: B) Cytotoxic T cells attacking transplanted cells --- 27. A key strategy to prevent immune rejection of stem cells is: A) Higher cell dose B) HLA matching between donor and recipient C) Stopping all immunosuppression D) Using unrelated donors Answer: B) HLA matching between donor and recipient --- 28. Autologous transplantation avoids rejection because: A) Cells are from an identical twin B) Cells are genetically modified C) Patient’s own cells are used D) Cells are from cord blood Answer: C) Patient’s own cells are used --- 30. The three germ layers are ectoderm, mesoderm, and: A) Epiderm B) Endoderm C) Periderm D) Blastoderm Answer: B) Endoderm --- 31. Muscle, bone, and blood arise from which germ layer? A) Ectoderm B) Endoderm C) Mesoderm D) Trophoderm Answer: C) Mesoderm --- 32. Nervous system and skin arise from: A) Ectoderm B) Mesoderm C) Endoderm D) Mesenchyme Answer: A) Ectoderm --- 33. During differentiation, stem cells undergo changes in: A) Gene expression only B) Morphology and metabolism only C) Gene expression, morphology, and metabolism D) None of the above Answer: C) Gene expression, morphology, and metabolism --- 36. Which stem cell source has lowest risk of GVHD? A) Bone marrow from unrelated donor B) Peripheral blood from sibling C) Umbilical cord blood D) All have same risk Answer: C) Umbilical cord blood --- 37. One major complication of pluripotent stem cells is: A) No differentiation ability B) Teratoma formation C) Cannot self‑renew D) No ethical concerns Answer: B) Teratoma formation --- 38. In regenerative medicine, stem cells are central because of their ability to: A) Only self‑renew B) Only differentiate C) Self‑renew and differentiate D) Cause inflammation Answer: C) Self‑renew and differentiate --- 39. Which disease is treated with bone marrow transplant as the oldest stem cell therapy? A) Parkinson’s B) Leukemia C) Spinal cord injury D) Osteoarthritis Answer: B) Leukemia --- 40. Future advances in stem cell therapy include all except: A) Gene editing B) Organoid technology C) Elimination of all immune reactions D) Biomaterials Answer: C) Elimination of all immune reactions --- 41. Steps of therapeutic stem cell transplantation in order: A) Conditioning → Collection → Infusion → Engraftment B) Collection → Conditioning → Infusion → Engraftment C) Infusion → Conditioning → Collection → Engraftment D) Engraftment → Collection → Conditioning → Infusion Answer: B) Collection → Conditioning → Infusion → Engraftment --- 42. The main therapeutic action of transplanted stem cells includes: A) Only replacing diseased cells B) Only immunomodulation C) Engraftment, regeneration, immunomodulation, and growth factor secretion D) Only growth factor secretion Answer: C) Engraftment, regeneration, immunomodulation, and growth factor secretion --- 43. Which stem cell type can generate any cell type (pluripotent)? A) HSC B) MSC C) ESC D) Cord blood HSC Answer: C) ESC --- 44. A clinical challenge for stem cell therapy in complex diseases is:

1. What is the minimum effective dose of CD34⁺ cells per kg for Hematopoietic Stem Cell Transplant (HSCT)? A) 1 × 10⁶ B) 2 × 10⁶ C) 4 × 10⁶ D) 8 × 10⁶ Answer: B) 2 × 10⁶ --- 2. The optimal dose of CD34⁺ cells per kg for HSCT is: A) 1–2 × 10⁶ B) 2–4 × 10⁶ C) 4–6 × 10⁶ D) 8–10 × 10⁶ Answer: C) 4–6 × 10⁶ --- 3. For a 70‑kg patient, the minimum total CD34⁺ cells required is approximately: A) 70 million B) 140 million C) 280 million D) 420 million Answer: B) 140 million --- 4. What is the target nucleated cell dose for bone marrow harvest? A) 1–2 × 10⁸/kg B) 2–3 × 10⁸/kg C) 4–6 × 10⁸/kg D) 1–2 × 10⁹/kg Answer: B) 2–3 × 10⁸/kg --- 5. Minimum nucleated cell dose for cord blood transplant is: A) 1.0 × 10⁷/kg B) 2.5 × 10⁷/kg C) 5.0 × 10⁷/kg D) 1.0 × 10⁸/kg Answer: B) 2.5 × 10⁷/kg --- 6. Common dose range for Mesenchymal Stem Cell (MSC) therapy in research/clinical trials is: A) 0.1–0.5 million cells/kg B) 1–10 million cells/kg C) 20–50 million cells/kg D) 100 million cells/kg Answer: B) 1–10 million cells/kg --- 7. Why does cell dose matter in stem cell transplantation? A) Higher dose always causes more GVHD B) Faster engraftment and lower graft failure C) Lower dose improves survival D) Dose does not affect outcome Answer: B) Faster engraftment and lower graft failure --- 8. Which disease type is most likely to be treatable with stem cells in the future? A) Complex multi‑factorial diseases B) Conditions caused by loss of a specific cell type C) Advanced neurodegenerative disorders D) Genetic diseases affecting many tissues Answer: B) Conditions caused by loss of a specific cell type --- 9. Which is a biological limitation for stem cell therapy? A) Too many donor cells available B) Difficulty controlling differentiation C) Excess immune tolerance D) Rapid integration with host tissue Answer: B) Difficulty controlling differentiation --- 10. Which stem cell type is well‑studied and widely used clinically for blood disorders? A) ESC B) iPSC C) MSC D) HSC Answer: D) HSC --- 11. A major limitation of Hematopoietic Stem Cells (HSCs) in allogeneic transplant is: A) High immune privilege B) Risk of GVHD C) Inability to form blood cells D) Ethical concerns Answer: B) Risk of GVHD --- 12. Which stem cell is known for low risk of immune rejection and secretes growth factors? A) ESC B) MSC C) HSC D) Cord blood stem cells Answer: B) MSC --- 13. A limitation of Mesenchymal Stem Cells is: A) High immunogenicity B) Unlimited differentiation potential C) Limited differentiation compared to pluripotent cells D) High tumor formation risk Answer: C) Limited differentiation compared to pluripotent cells --- 14. Embryonic Stem Cells (ESCs) are derived from: A) Adult bone marrow B) Umbilical cord blood C) Inner cell mass of blastocysts D) Reprogrammed skin cells Answer: C) Inner cell mass of blastocysts --- 15. A major ethical issue with ESCs is: A) They cannot differentiate B) Embryo destruction C) They cause GVHD D) They are patient‑specific Answer: B) Embryo destruction --- 16. Risk of tumor formation (teratomas) is associated with: A) HSC B) MSC C) ESC and iPSC D) Cord blood stem cells Answer: C) ESC and iPSC --- 17. Induced Pluripotent Stem Cells (iPSCs) are derived from: A) Blastocyst inner cell mass B) Fetal liver C) Reprogrammed adult somatic cells D) Cord blood Answer: C) Reprogrammed adult somatic cells --- 18. Main advantage of iPSCs over ESCs is: A) No genetic instability B) Avoids ethical issues of embryo use C) Higher teratoma risk D) Easier differentiation into all germ layers Answer: B) Avoids ethical issues of embryo use --- 19. Limitation of umbilical cord blood stem cells for adults is: A) High GVHD risk B) Limited cell numbers C) Difficult collection D) Cannot form blood cells Answer: B) Limited cell numbers --- 21. Graft‑versus‑Host Disease (GVHD) is caused by: A) Recipient’s immune cells attacking donor cells B) Donor immune cells attacking recipient’s tissues C) Stem cells failing to engraft D) Chemotherapy toxicity

اني ما عندي الملازم فياريت الي عنده لا يقصر ويه زميلنا 🙏🏻

سلام عليكم اريد المادة الداخلة بامتحان علم الدم ٢ للمحملين من المرحلة الثالثة؟

B) Antibiotics, steroids, and certain cancer drugs C) Vitamins D) Pain relievers like ibuprofen Answer: B) Antibiotics, steroids, and certain cancer drugs --- 16. Which treatment or procedure can provide additional ways for germs to enter the body? A) Oral medication B) Urinary catheters and surgery C) Physical therapy D) Routine blood pressure check Answer: B) Urinary catheters and surgery --- 17. What should patients and caregivers do often to prevent infection? A) Avoid all contact with healthcare staff B) Wash hands with soap and water or use alcohol-based hand sanitizer C) Take antibiotics daily D) Wear gloves at all times Answer: B) Wash hands with soap and water or use alcohol-based hand sanitizer --- 18. Patients and caregivers can remind healthcare staff to: A) Speak loudly B) Clean their hands before touching the patient C) Avoid using medical devices D) Change bed linens daily Answer: B) Clean their hands before touching the patient --- 19. What is recommended for all frontline healthcare workers? A) Daily antibiotic prophylaxis B) Accessible infection control education C) Avoiding direct patient contact D) Using only alcohol-based hand rubs without washing Answer: B) Accessible infection control education --- 20. Healthcare facilities should assess and improve their: A) Parking lot cleanliness B) Infection control and prevention practices C) Cafeteria menu options D) Uniform color policy Answer: B) Infection control and prevention practices --- 21. What is one action healthcare facilities should consider to reduce water-based health risks? A) Remove all sinks B) Increase water pressure C) Specific actions to reduce water-based risks (per lecture recommendation) D) Boil all tap water Answer: C) Specific actions to reduce water-based risks (per lecture recommendation) --- 22. What does MDRO stand for? A) Multi-Drug Resistant Organisms B) Medical Device Regulation Order C) Multiple Disease Response Outbreak D) Microbial Detection and Removal Operation Answer: A) Multi-Drug Resistant Organisms --- 23. Strategies for preventing MDROs include: A) Using more antibiotics B) Preventing and responding to multi-drug resistant organisms C) Stopping all hand hygiene D) Avoiding isolation of infected patients Answer: B) Preventing and responding to multi-drug resistant organisms --- 24. Which of the following is NOT a source of germs mentioned in the lecture? A) Cooling towers B) Faucets and sinks C) Clean, dry air D) Dust or decaying debris Answer: C) Clean, dry air --- 25. A person who has cancer and is on chemotherapy is likely to be: A) More resistant to all infections B) A susceptible person C) Unable to transmit germs D) Always colonized Answer: B) A susceptible person --- 26. Germs depend on which of the following to move in healthcare settings? A) Only patients B) People, the environment, and medical equipment C) Only airborne currents D) Only unclean water Answer: B) People, the environment, and medical equipment --- 27. For an infection to occur, germs must do all of the following EXCEPT: A) Transmit from a source to a person B) Enter the body C) Invade tissues and multiply D) Cause the person to be hospitalized Answer: D) Cause the person to be hospitalized --- 28. Which is an example of a moist environment source of germs? A) A dry countertop B) Collections of microorganisms inside pipes C) A sterile syringe D) A patient's hair Answer: B) Collections of microorganisms inside pipes --- 29. What should healthcare facilities do regarding MDROs? A) Ignore them if no symptoms are present B) Use only one type of antibiotic C) Have strategies for preventing and responding to them D) Isolate all patients Answer: C) Have strategies for preventing and responding to them