Embryology — MCQs Biology 50 min Score: 0 Attempted: 0/50 Subscribe 1. Embryology is the study of: (A) Genetics only (B) Cell division only (C) Development of an organism from fertilization to birth (D) Tissue repair only 2. Fertilization is the process of: (A) Formation of tissues (B) Cell division (C) Fusion of male and female gametes (D) Photosynthesis 3. Zygote is: (A) The first cell formed after fertilization (B) A tissue (C) A multicellular embryo (D) A gamete 4. Cleavage refers to: (A) Organ formation (B) Cell differentiation (C) Rapid mitotic divisions of the zygote (D) Gamete formation 5. Blastula is: (A) Tissue layer (B) Single-celled zygote (C) Fully formed organ (D) Hollow ball of cells after cleavage 6. Blastocoel is: (A) Nucleus (B) Fluid-filled cavity in the blastula (C) Cytoplasm (D) Cell membrane 7. Gastrulation is the process that forms: (A) Gametes (B) Single-layered blastula (C) Zygote (D) Three germ layers 8. The three primary germ layers are: (A) Endoderm, exoderm, mesoderm (B) Ectoderm, mesoderm, exoderm (C) Ectoderm, mesoderm, endoderm (D) Mesoderm, epiderm, endoderm 9. Ectoderm gives rise to: (A) Muscles only (B) Nervous system and skin (C) Bones only (D) Digestive organs only 10. Mesoderm gives rise to: (A) Muscles, skeleton, circulatory system (B) Nervous system only (C) Skin only (D) Digestive tract only 11. Endoderm gives rise to: (A) Bones only (B) Nervous system only (C) Gut lining, liver, pancreas (D) Muscles only 12. Neurulation results in: (A) Gut formation (B) Heart formation (C) Limb buds (D) Formation of neural tube 13. Neural crest cells give rise to: (A) Peripheral nervous system, melanocytes, facial cartilage (B) Heart only (C) Liver only (D) Gut only 14. Somitogenesis forms: (A) Somites which develop into vertebrae and muscles (B) Neural tube (C) Skin only (D) Digestive tract 15. Morphogens are: (A) Muscle fibers (B) Molecules that guide tissue patterning (C) DNA only (D) Energy molecules only 16. Hox genes regulate: (A) Body segment identity (B) Energy production (C) Photosynthesis (D) Protein synthesis only 17. Organogenesis refers to: (A) Cell division only (B) Formation of organs from germ layers (C) Fertilization (D) Cleavage only 18. Limb bud formation is controlled by: (A) Neural tube only (B) Apical ectodermal ridge (AER) (C) Somites only (D) Endoderm only 19. Sonic hedgehog (Shh) gene controls: (A) Limb and neural patterning (B) Photosynthesis (C) DNA replication only (D) Energy metabolism 20. Wnt signaling pathway regulates: (A) Photosynthesis (B) Cell fate and patterning (C) DNA replication (D) Energy production only 21. Notch signaling pathway is involved in: (A) Cell differentiation and tissue development (B) Energy production only (C) DNA replication only (D) Photosynthesis only 22. Apoptosis during embryogenesis is: (A) DNA replication (B) Random cell death (C) Cell division (D) Programmed cell death for shaping tissues 23. Blastocyst implantation occurs in: (A) Ovary (B) Uterus (C) Fallopian tube (D) Vagina 24. Extraembryonic membranes include: (A) Only yolk sac (B) Only amnion (C) Only chorion (D) Amnion, chorion, yolk sac, allantois 25. Amnion functions to: (A) Form muscles (B) Form bones (C) Cushion and protect embryo (D) Produce energy 26. Allantois functions in: (A) Energy production only (B) Waste storage and gas exchange (C) Muscle formation (D) Photosynthesis 27. Chorion functions in: (A) Gas exchange and placenta formation (B) Energy production (C) Photosynthesis only (D) DNA replication only 28. Yolk sac functions in: (A) Waste excretion only (B) Early nutrition (C) Energy only (D) Photosynthesis 29. Totipotent cells can: (A) Form only muscles (B) Form only one tissue type (C) Form only gametes (D) Give rise to all cell types including extraembryonic tissues 30. Pluripotent cells can: (A) Form only neural tissue (B) Form only muscles (C) Form gametes only (D) Form all body cell types but not extraembryonic tissues 31. Multipotent cells can: (A) Form gametes only (B) Form all tissues (C) Differentiate into a limited number of cell types (D) Form neurons only 32. Induction in embryology refers to: (A) Photosynthesis (B) Random mutation (C) DNA replication (D) Influence of one cell group on another for differentiation 33. Competence in cells means: (A) Ability to respond to inductive signals (B) Ability to divide only (C) Ability to photosynthesize (D) Ability to produce energy 34. Determination in embryogenesis is: (A) Energy production (B) Random cell division (C) DNA replication only (D) Commitment of cells to a specific fate 35. Blastopore in protostomes forms: (A) Mouth (B) Anus (C) Neural tube (D) Heart 36. Blastopore in deuterostomes forms: (A) Heart (B) Mouth (C) Anus (D) Muscles 37. Epigenesis theory states: (A) Organisms develop from simple to complex structures (B) Organisms preexist in miniature (C) Development is random (D) Only DNA controls development 38. Preformation theory suggested: (A) DNA controls everything (B) Development is gradual (C) Embryos are random (D) Organisms develop from miniature version in gametes 39. Cleavage in amphibians is: (A) Holoblastic and radial (B) Meroblastic only (C) Superficial only (D) Spiral only 40. Cleavage in birds is: (A) Superficial only (B) Holoblastic only (C) Spiral only (D) Meroblastic and discoidal 41. Mammalian cleavage is: (A) Meroblastic only (B) Holoblastic and rotational (C) Spiral only (D) Radial only 42. Human gastrulation occurs in: (A) Third week (B) First week (C) Second week (D) Fourth week 43. Extraembryonic membranes are derived from: (A) Mesoderm only (B) Endoderm only (C) Trophoblast and embryonic tissues (D) Ectoderm only 44. Amniotic fluid is secreted by: (A) Amnion and maternal tissues (B) Yolk sac only (C) Chorion only (D) Allantois only 45. Chorionic villi participate in: (A) Bone formation only (B) Photosynthesis (C) Muscle formation only (D) Maternal-fetal nutrient and gas exchange 46. Extraembryonic coelom is formed between: (A) Amnion and chorion (B) Yolk sac and chorion (C) Embryo and amnion (D) Chorion and uterus 47. Human placentation type is: (A) Diffuse only (B) Zonary only (C) Discoidal and hemochorial (D) Cotyledonary only 48. Teratogens affect: (A) DNA replication only (B) Energy production (C) Photosynthesis (D) Normal development of embryo 49. Fetal period in humans starts from: (A) Fifth week (B) First week (C) Third week (D) Ninth week of gestation 50. Organogenesis in humans is mostly completed by: (A) Tenth week (B) First week (C) Third week (D) End of eighth week