Gametogenesis, fertilization, embryo development, gastrulation - Question Bank

1. Which of the following is an example of induction during embryonic development?
A) Sperm penetrating the zona pellucida
B) Cells migrating to form germ layers
C) The notochord inducing the formation of the neural tube
D) The zygote undergoing rapid cell division
2. The formation of the neural tube from the ectoderm is a crucial part of:
A) Gastrulation
B) Neurulation
C) Organogenesis
D) Blastulation
3. What is the fate of the blastocoel during gastrulation?
A) It expands to form the amniotic cavity
B) It is obliterated as germ layers form
C) It develops into the archenteron
D) It forms the primary coelom
4. The second meiotic division in oogenesis is completed only upon:
A) Ovulation
B) Fertilization by sperm
C) Implantation
D) Gastrulation
5. The first meiotic division in oogenesis produces a large secondary oocyte and a small:
A) Oogonium
B) First polar body
C) Second polar body
D) Ovum
6. What is the primary role of the sperm's acrosome?
A) Provide energy for motility
B) Contain enzymes to penetrate egg coats
C) Carry the paternal DNA
D) Facilitate fusion with the egg membrane
7. The formation of somites, blocks of mesoderm that give rise to vertebrae and muscles, is called:
A) Neurulation
B) Gastrulation
C) Somitogenesis
D) Organogenesis
8. What is the process of sperm maturation that occurs in the female reproductive tract, enabling it to fertilize an egg?
A) Acrosome reaction
B) Capacitation
C) Cortical reaction
D) Syngamy
9. The primitive gut formed during gastrulation is known as the:
A) Archenteron
B) Blastocoel
C) Coelom
D) Morula
10. The epiblast and hypoblast are layers present in the blastocyst of which organism?
A) Sea urchin
B) Amphibian
C) Bird
D) Mammal
11. What is the term for the formation of the three germ layers from the blastoderm in a bird embryo?
A) Cleavage
B) Blastulation
C) Gastrulation
D) Organogenesis
12. The invagination of cells to form the archenteron during gastrulation in sea urchins is an example of:
A) Epiboly
B) Involution
C) Ingression
D) Delamination
13. In sea urchins, the first opening formed during gastrulation is called the:
A) Blastopore
B) Archenteron
C) Blastocoel
D) Protostome
14. The process by which cells become specialized in structure and function is called:
A) Cleavage
B) Gastrulation
C) Fertilization
D) Differentiation
15. What is the first sign of embryonic development after fertilization?
A) Formation of the blastocyst
B) Beginning of cleavage
C) Differentiation of germ layers
D) Implantation
16. The allantois in amniotes functions in:
A) Gas exchange and waste storage
B) Nutrient absorption
C) Protection from mechanical shock
D) Formation of the digestive tract
17. The yolk sac primarily functions to provide nutrients to the developing embryo in which group of animals?
A) Mammals
B) Birds
C) Amphibians
D) All of the above
18. Which extraembryonic membrane contributes to the formation of the placenta in mammals?
A) Amnion
B) Yolk sac
C) Chorion
D) Allantois
19. The extraembryonic membrane that encloses the embryo in amniotic fluid is the:
A) Chorion
B) Allantois
C) Yolk sac
D) Amnion
20. In human development, implantation typically occurs around which day post-fertilization?
A) Day 1-2
B) Day 3-4
C) Day 6-7
D) Day 10-12
21. What is the process of implantation of the embryo into the uterine wall?
A) Gastrulation
B) Ovulation
C) Implantation
D) Parturition
22. The initial formation of the nervous system from the ectoderm is called:
A) Neurulation
B) Somitogenesis
C) Gastrulation
D) Argyrophilia
23. What is the term for the development of specialized cells and tissues from the germ layers?
A) Gastrulation
B) Organogenesis
C) Fertilization
D) Cleavage
24. The process where cells change their shape and position to form the germ layers is called:
A) Cell differentiation
B) Morphogenesis
C) Blastulation
D) Induction
25. Which structure forms the anterior end of the primitive streak in avian embryos, signaling the formation of the head?
A) Kopfer's node
B) Hensen's node
C) Primitive groove
D) Blastopore
26. In chick embryo development, gastrulation involves the formation of a primitive streak and:
A) Hensen's node
B) Blastocoel
C) Amnion
D) Chorion
27. The inner germ layer that forms the lining of the digestive tract and respiratory system is the:
A) Ectoderm
B) Mesoderm
C) Endoderm
D) Mesentery
28. The middle germ layer that forms muscles, bones, and circulatory system is the:
A) Ectoderm
B) Endoderm
C) Mesoderm
D) Epidermis
29. The outer germ layer that gives rise to the nervous system and epidermis is the:
A) Endoderm
B) Mesoderm
C) Ectoderm
D) Mesoglea
30. Which of the following is NOT one of the three primary germ layers formed during gastrulation?
A) Ectoderm
B) Mesoderm
C) Endoderm
D) Blastocoel
31. What is the process by which the three primary germ layers are formed?
A) Cleavage
B) Blastulation
C) Gastrulation
D) Organogenesis
32. The outer layer of the blastocyst that contributes to the placenta is called the:
A) Inner cell mass
B) Trophoblast
C) Epiblast
D) Hypoblast
33. The inner cell mass of the blastocyst will eventually form the:
A) Trophoblast
B) Embryo proper
C) Placenta
D) Yolk sac
34. In mammalian development, the blastula is specifically called a:
A) Morula
B) Gastrula
C) Blastocyst
D) Zygote
35. What is the hollow ball of cells that forms after the morula stage?
A) Zygote
B) Gastrula
C) Blastula
D) Embryo
36. A solid ball of cells formed after several rounds of cleavage is called a:
A) Blastula
B) Morula
C) Gastrula
D) Zygote
37. What is the rapid series of mitotic cell divisions that occur in the zygote?
A) Gastrulation
B) Organogenesis
C) Cleavage
D) Implantation
38. What is the term for the first cell formed after fertilization?
A) Blastocyst
B) Morula
C) Zygote
D) Embryo
39. What is the physiological block to polyspermy, preventing multiple sperm from fertilizing one egg?
A) Cortical reaction
B) Zona reaction
C) Acrosome reaction
D) Capacitation
40. The acrosome reaction involves the release of enzymes that help the sperm penetrate which layers of the egg?
A) Zona pellucida and Corona radiata
B) Corona radiata and Vitelline membrane
C) Zona pellucida and Vitelline membrane
D) Corona radiata and Cumulus oophorus
41. What is the glycoprotein layer surrounding the mammalian egg that sperm must penetrate?
A) Corona radiata
B) Zona pellucida
C) Vitelline membrane
D) Cumulus oophorus
42. In mammals, where does fertilization typically occur?
A) Ovary
B) Uterus
C) Fallopian tube (Oviduct)
D) Vagina
43. What is the fusion of male and female gametes called?
A) Oogenesis
B) Spermatogenesis
C) Fertilization
D) Cleavage
44. Which cell is released from the ovary during ovulation, and is arrested in Metaphase II of meiosis?
A) Primary oocyte
B) Secondary oocyte
C) Ovum
D) Oogonium
45. What is the unequal division of cytoplasm during oogenesis called?
A) Holoblastic cleavage
B) Meroblastic cleavage
C) Polar body formation
D) Synapsis
46. In oogenesis, what is the diploid cell that begins meiosis and is arrested in Prophase I?
A) Oogonium
B) Primary oocyte
C) Secondary oocyte
D) Ovum
47. What is the final product of spermatogenesis?
A) Spermatogonium
B) Spermatid
C) Spermatozoon
D) Secondary spermatocyte
48. Which stage of meiosis involves homologous chromosomes pairing up and crossing over?
A) Prophase I
B) Metaphase I
C) Anaphase I
D) Telophase I
49. In spermatogenesis, what is the diploid cell that undergoes meiosis to produce spermatids?
A) Spermatogonium
B) Primary spermatocyte
C) Secondary spermatocyte
D) Spermatid
50. What is the primary process by which germ cells (sperm and egg) are produced?
A) Mitosis
B) Meiosis
C) Cytokinesis
D) Amitosis