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