EXAM ONE

Short answer- up to one paragraph each.



As long as the answer is understandable, you will not lose points for spelling or grammar. Open note and open book. You do not need to use citations as long as you are writing from memory and your notes. 4 points per question



Module one





1. What is the difference between growth and development?

2. What is the difference between a zygote and an embryo?

3. What are the two hemispheres of the frog yolk and what is the role of each?

4. The typical frog has 7 developmental stages. List two of those stages and one important event that occurs each of those two stages.

5. Define and present an example of a embryonic homology

6. Define and present an example of a embryonic analogy

7. What is a teratogen? Provide one example



Module two





1. In a few sentences, explain von Leeuwenhoek’s hypothesis about the role of sperm in embryogenesis.

2. List and describe (1 -2 sentences) four ways the mammalian female reproductive tract influences sperm motility.

3. Three reasons why sea urchins are used as a model in fertilization studies.

4. Outline one model of how chemotaxis explains sperm attraction to the egg.

5. List 3 ways that polyspermy is prevented.

6. List and define (with 1-2 sentences) the five basic steps of recognition of sperm and egg.



Module Three





1. List 3 reasons why the zebrafish is an important model in early development studies.

2. How does amphibian cleavage and gastrulation differ from the zebrafish model?

3. In a few sentences explain the development of the mesoderm in an animals, avian, amphibian or fish model.

4. What is the primitive streak?

5. What is compaction?

6. Contrast the monozygotic and the dizygotic twin from fertilization to birth, including 3 distinct points of difference.

7. Of the three vertebrate classes we have considered, which has been the most difficult for scientists to study during the gastrulation phase? List three reasons.

8. Compare neural tube development in birds and fish.

List at least one characteristic unique to each and one common to each.

9. Compare neural tube development in mammals and amphibians. List at least one characteristic unique to each and one common to each.

10. Mammals have left-right axis development. List some distinctions between the left and right sides of a mammal 298

11. Define cleavage and rotational cleavage. 300

12. Unlike birds, fish , and amphibians, mammal embryos do not have a yolk. How do they compensate for the absence of a yolk? 305