Embryo Questions PDF

Q65. During implantation, the blastocyst attaches to the endometrial lining through which layer? a\) Epiblast b\) Hypoblast c\) Syncytiotrophoblast d\) Cytotrophoblast Answer: c) Syncytiotrophoblast Q66. The extra-embryonic mesoderm contributes to the formation of which structure during the se...

Q65. During implantation, the blastocyst attaches to the endometrial lining through which layer? a\) Epiblast b\) Hypoblast c\) Syncytiotrophoblast d\) Cytotrophoblast Answer: c) Syncytiotrophoblast Q66. The extra-embryonic mesoderm contributes to the formation of which structure during the second week? a\) Amniotic sac b\) Placenta c\) Neural tube d\) Somites Answer: b) Placenta Q67. Which of the following structures forms from the epiblast during the second week of development? a\) Amniotic cavity b\) Yolk sac c\) Trophoblast d\) Hypoblast Answer: a) Amniotic cavity Q68. Which of the following is derived from the ectoderm? a\) Skin and nervous system b\) Muscles and bones c\) Liver and pancreas d\) Heart and blood vessels Answer: a) Skin and nervous system Q69. The process of neurulation results in the formation of which structure? a\) Neural tube b\) Somites c\) Notochord d\) Pharyngeal arches Answer: a) Neural tube Q71. The neural tube closes by the end of which week of development? a\) Week 2 b\) Week 3 c\) Week 4 d\) Week 5 Answer: c) Week 4 Q74. The placental barrier consists of which of the following layers? a\) Cytotrophoblast, syncytiotrophoblast, and fetal capillary endothelium b\) Epiblast, hypoblast, and trophoblast c\) Endoderm, ectoderm, and mesoderm d\) Maternal blood vessels and fetal blood vessels Answer: a) Cytotrophoblast, syncytiotrophoblast, and fetal capillary endothelium Q75. The umbilical cord is composed of: a\) Two arteries and one vein b\) One artery and two veins c\) Three arteries and one vein d\) One artery and one vein Answer: a) Two arteries and one vein Q76. Which of the following teratogens is known to cause limb defects if a pregnant woman is exposed during the critical period? a\) Alcohol b\) Rubella virus c\) Thalidomide d\) Folic acid deficiency Answer: c) Thalidomide Q77. A child born with a cleft palate is most likely to have been exposed to which teratogen during the first trimester? a\) Alcohol b\) Radiation c\) Rubella virus d\) Retinoic acid Answer: d) Retinoic acid Q78. Which of the following prenatal tests is most commonly used to assess the structure of the fetus at various stages of pregnancy? a\) Amniocentesis b\) Chorionic villus sampling c\) Ultrasound d\) Non-invasive prenatal testing (NIPT) Answer: c) Ultrasound Q79. Chorionic villus sampling is typically performed during which week of pregnancy? a\) Week 8-10 b\) Week 12-14 c\) Week 16-18 d\) Week 20-22 Answer: b) Week 12-14 Q80. A 28-year-old pregnant woman comes for her first prenatal check-up at 16 weeks of gestation. She has a family history of sickle cell disease and requests genetic testing. What is the most appropriate prenatal diagnostic test for her? a\) Amniocentesis b\) Chorionic villus sampling c\) Non-invasive prenatal testing (NIPT) d\) Carrier screening for sickle cell disease Answer: d) Carrier screening for sickle cell disease Q81. A 24-year-old woman in her first trimester presents to the emergency room with severe abdominal pain and light vaginal bleeding. Ultrasound confirms a miscarriage. The patient is concerned about future pregnancies. What is the most appropriate next step to assess her reproductive health? a\) Karyotyping b\) Serum progesterone levels c\) Hysterosalpingography d\) Genetic counseling Answer: b) Serum progesterone levels Q82. The embryonic period ends at the: a\) 8th week b\) 12th week c\) 20th week d\) 24th week Answer: a) 8th week Q83. The term \"gestational age\" refers to: a\) The age of the fetus based on its development b\) The age of the embryo from fertilization c\) The age of the fetus from the first day of the last menstrual period d\) The time from fertilization to the birth of the baby Answer: c) The age of the fetus from the first day of the last menstrual period Q84. The Sertoli cells in the male reproductive system are primarily responsible for: a\) Producing testosterone b\) Supporting and nourishing sperm cells c\) Stimulating sperm maturation d\) Secreting seminal fluid Answer: b) Supporting and nourishing sperm cells Q86. In which phase of meiosis does genetic recombination occur? a\) Prophase I b\) Metaphase I c\) Anaphase I d\) Telophase II Answer: a) Prophase I Q87. Which of the following best describes the difference between meiosis I and meiosis II? a\) Meiosis I separates sister chromatids, while meiosis II separates homologous chromosomes. b\) Meiosis I results in the formation of two daughter cells, while meiosis II results in four daughter cells. c\) Meiosis I involves crossing-over, while meiosis II does not. d\) Meiosis II produces haploid cells, while meiosis I produces diploid cells. Answer: b) Meiosis I results in the formation of two daughter cells, while meiosis II results in four daughter cells. Q88. Which of the following best describes spermatogenesis? a\) The process where one diploid germ cell produces one functional sperm. b\) The process of oocyte formation in females. c\) The process where one diploid germ cell produces four functional sperm. d\) The formation of eggs in females that are arrested in metaphase II. Answer: c) The process where one diploid germ cell produces four functional sperm. Q89. In females, the first meiotic division of oogenesis results in: a\) One primary oocyte and three polar bodies b\) Two secondary oocytes c\) One secondary oocyte and one polar body d\) Two polar bodies and one oocyte Answer: c) One secondary oocyte and one polar body Q90. Fertilization normally occurs in which part of the female reproductive system? a\) Uterus b\) Ovary c\) Fallopian tube d\) Cervix Answer: c) Fallopian tube Q91. The zona pellucida is important in fertilization because it: a\) Prevents the embryo from implanting prematurely. b\) Stimulates sperm motility. c\) Prevents polyspermy by blocking the entry of additional sperm. d\) Is the site of maternal blood exchange. Answer: c) Prevents polyspermy by blocking the entry of additional sperm. Q92. The inner cell mass of the blastocyst differentiates into: a\) The epiblast and hypoblast b\) The ectoderm and mesoderm c\) The trophoblast and cytotrophoblast d\) The somatic and splanchnic mesoderm Answer: a) The epiblast and hypoblast Q93. The cytotrophoblast and syncytiotrophoblast are derived from: a\) Epiblast b\) Hypoblast c\) Trophoblast d\) Extra-embryonic mesoderm Answer: c) Trophoblast Q94. The notochord is derived from which germ layer? a\) Ectoderm b\) Mesoderm c\) Endoderm d\) Epiblast Answer: b) Mesoderm Q95. The process of somite formation occurs during which phase of embryonic development? a\) Early gastrulation b\) Late gastrulation c\) Organogenesis d\) Neurulation Answer: b) Late gastrulation Q96. By the end of which week do the basic body plan and organ systems begin to form? a\) Week 3 b\) Week 4 c\) Week 6 d\) Week 8 Answer: b) Week 4 Q97. The heart starts to beat by which day of embryonic development? a\) Day 16 b\) Day 20 c\) Day 22 d\) Day 28 Answer: c) Day 22 Q98. The development of fetal limbs occurs during which month of pregnancy? a\) 1st month b\) 2nd month c\) 3rd month d\) 4th month Answer: b) 2nd month Q99. By the end of the 3rd trimester, the fetus has reached what approximate length? a\) 30 cm b\) 40 cm c\) 50 cm d\) 60 cm Answer: c) 50 cm Q100. Which of the following is responsible for nutrient and waste exchange between the mother and fetus? a\) Chorion b\) Amniotic sac c\) Placenta d\) Yolk sac Answer: c) Placenta Q101. The amniotic fluid serves all of the following functions except: a\) Cushioning the fetus b\) Maintaining a constant temperature c\) Assisting in the development of the lungs d\) Providing nutrients to the fetus Answer: d) Providing nutrients to the fetus Q102. Which of the following genetic conditions is most likely associated with maternal age over 35 years? a\) Down syndrome b\) Turner syndrome c\) Klinefelter syndrome d\) Cystic fibrosis Answer: a) Down syndrome Q103. Teratogenic effects of alcohol during pregnancy may result in which of the following? a\) Cleft lip and palate b\) Spina bifida c\) Fetal alcohol syndrome d\) Clubfoot Answer: c) Fetal alcohol syndrome 12\. Antenatal Diagnostic Techniques (Continued) Q104. The most common indication for amniocentesis is to: a\) Screen for neural tube defects b\) Assess fetal lung maturity c\) Detect genetic disorders d\) Determine fetal position Answer: c) Detect genetic disorders Q105. Non-invasive prenatal testing (NIPT) can detect which of the following conditions? a\) Cystic fibrosis b\) Neural tube defects c\) Chromosomal abnormalities, including Down syndrome d\) Spina bifida Answer: c) Chromosomal abnormalities, including Down syndrome Q106. A 30-year-old pregnant woman at 20 weeks gestation presents for routine prenatal care. Her ultrasound shows a low-lying placenta. What is the likely outcome for this pregnancy? a\) Increased risk of preterm labor b\) Need for immediate cesarean section c\) Placenta will likely move up as pregnancy progresses d\) Increased risk of maternal hypertension Answer: c) Placenta will likely move up as pregnancy progresses Q107. A woman with a history of multiple miscarriages is found to have a bicornuate uterus. What is the most appropriate management for her pregnancy? a\) Bed rest and frequent ultrasounds b\) Surgical correction of the uterine anomaly c\) Close monitoring for preterm labor d\) No intervention, as the pregnancy will likely proceed without complications Answer: c) Close monitoring for preterm labor