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Study Guide for Developmental Biology Midterm Exam.

Chapter 7 Fertilization

1. Be able to list the four major events that occur during fertilization.  Know and understand what is happening during each major event.
2. Know the anatomy of a mammalian sperm.  Know which part of the mammalian sperm contains the acrosome, nucleus, mitochondria, centriole and axoneme.
3. Understand the anatomy of an axoneme to the extent we went over in class.
4. Describe Kartagener triad and how it is caused.
5. List the things that oocytes and eggs stockpile in their cytoplasm.
6. Define structural features of the sea urchin egg such as the vitelline envelope, cortical granule and egg jelly.
7. List the steps of sea urchin egg-sperm recognition.
8. List the steps of mammalian secondary oocyte-sperm recognition.
9. Describe the two steps involved in the acrosome reaction in sea urchins.
10. Pertaining to the acrosome reaction in sea urchins, describe the role(s) of the acrosomal vesicle, the acrosomal processs, bindin and bindin receptors.
11. Explain the role of the zona pellucida in mammalian secondary oocyte-sperm recognition.
12. What is the mammalian zona pellucida and where is it found?
13. Know the role of the Zp3 glycoprotein of the zona pellucida in oocyte-sperm recognition.
14. Explain the role of the acrosomal process in sea urchin gamete fusion.
15. Explain what happens during the fast block to polyspermy in sea urchins.
16. Describe the steps during the slow block to polyspermy in sea urchins.
17. Understand that sea urchins have the slow block to polyspermy but mammals do not.  Both sea urchins and mammals undergo the slow block to polyspermy.
18. Describe what is happening during the cortical granule reaction.  How is the smooth endoplasmic reticulum involved in the cortical granule reaction?
19. Know what increases egg cell metabolism.  Namely, the increase of intracellular calcium levels and an increase in intracellular pH increases egg cell metabolism.

Chapter 8 Early Sea Urchin Development

1. Know why sea urchin cleavage is considered holoblastic.
2. Be able to list in order the stages of early sea urchin embryogenesis from the cleavage stage to the pluteus larva stage.
3. Know the difference between meridional cleavage and equatorial cleavage.
4. Study figure 8.7.  Know what type of cleavage (meridional or equatorial) is occurring doing the first, second and third cleavage events.
5. Indicate where the mesomeres, micromeres and macromeres are found in the early sea urchin embryo.
6. Be able to indicate that ectodermal tissue develops from animal hemisphere-derived cells and that mesodermal and endodermal tissue develops from vegetal hemisphere-derived cells.
7. Draw a sea urchin blastula.  Indicate where the blastocoel is found.
8. What event begins gastrulation in sea urchins?  The answer is the ingression of primary mesenchyme cells into the blastocoel.
9. Describe the role of the secondary mesenchyme cells during sea urchin gastrulation.
10. Know that the primary mesenchyme cells derive from the micromeres and the secondary mesenchyme cells derive from the veg2 cells.
11. Know that at the end of gastrulation, the three germ layers are formed. 
12. List the three germ layers and indicate which layer is the outer layer, which layer is the middle layer and which layer is the inner layer.
13. What is the archenteron and during which stage of sea urchin embryogenesis is it formed?
14. What is the blastopore?
15. What is invagination and in what part of the sea urchin embryo does invagination begin?
16. Identify sea urchin embryonic stages and specific structures in each embryonic stage.

Chapters 2 and 10.  Early Amphibian Development

1. Know the stages of early amphibian development in order.  Cleavage, blastula, gastrula and organogenesis.
2. Describe frog oocyte maturation and the role of progesterone in frog oocyte maturation.
3. Know the similarities and differences of frog embryo cleavage compared to that of sea urchin embryo cleavage.  For example, cleavage in both types of embryos is holoblastic.  However, in frogs, latter cleavages begin before earlier cleavages have been completed.
4. Explain why in frogs the latter cleavages begin before the earlier cleavages have been completed.
5. Describe gastrulation in frogs.  Gastrulation begins at the marginal zone.  Where is the marginal zone located in a frog embryo?
6. What is the dorsal blastopore lip and the blastopore?
7. Describe the process of epiboly.
8. What is the yolk plug?
9. Describe the process of neurulation in frogs.  For instance, underlying mesoderm cells called the notochord tell the ectodermal cells above them to form into neural folds.  The neural folds come together forming the neural tube.  The neural tube forms the frog’s nervous system.
10. Define the following terms:  notochord, neural tube and somites.
11. Somites are the precursors to what tissues in frogs?
12. What is a Deuterostome?  Know that sea urhins and vertebrates are deuterostomes.
13. What is a Protostome?  Know that worms and mollusks are protostomes.
14. Identify frog embryonic stages and specific structures of a specific embryonic stage.

Chapter 11 Early Development in Birds

1. Explain why chick cleavage is considered to be discoidal meroblastic.
2. Why are fish and bird eggs called telolecithal?
3. Define the following terms used when the chick embryo is in the cleavage stage:  blastoderm, Koller’s sickle region, area pellucida, subgerminal space, area opaca and primary hypoblast cells.
4. Realize that the chick embryo is considered to be in the blastula stage when the embryo consists of an epiblast layer and a hypoblast layer with a blastocoel located between them.
5. Indicate when gastrulation begins in chick embryos.  Gastrulation begins with the primitive streak formation.  The primitive streak is first noticed as a visible thickening of the epiblast just anterior to Koller’s sickle.
6. Define the following terms used when the chick embryo is in the gastrula stage:  Primitive groove, Henson’s node and Head process.
7.  Explain why organogenesis and gastrulation can occur at the same time in an early chick embryo.
8. Identify different chick embryologic stages and specific structures within a given embryonic stage.
9. Why is mammalian cleavage considered to be rotational?
10. Know the differences in mammalian embryo cleavage compared to that of other organisms.
11. What is compaction?
12. What is cavitation?
13. Which cell type is involved in blastocyst hatching?
14. Which cell type is involved in allowing a mammalian embryo to implant in the uterine wall?
15. Know the roles of the yolk sac, amniotic sac and the allantois during embryonic development.
16. Review slide 27 (monozygotic twin formation).
17. Where do the various religions we discussed in class stand on when human life begins?
18. How does one go about making chimeric mice?
19. Cite evidence for human chimeras.
20. List and describe ways that non-identical monozygotic twins can form.