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1. The number of eggs produced by the members of a species can be related to the amount of care given to the developing young.Is the same true of the number of sperm produced?Explain.

2. The retention of fertilized eggs within the motherís body occurs commonly among the cartilaginous fishes and reptiles.Why do you suppose no birds employ this means of protecting their young?

3. Where does fertilization occur in the (a) trout, (b) shark, (c) queen bee, (d) frog, and (e) human?

4. Few animals have both male and female sex organs, while most plants do.Can you think of any explanation for this?

5. Explain why animals that develop by means of parthenogenesis are usually female.

6. In what ways are the process of regeneration and embryonic development similar?In what way are they different?

7. From what embryonic germ layer is the optic nerve derived?

8. Distinguish between identical and fraternal twins.

9. A tadpole ready to hatch is slightly larger than the fertilized egg was.What might account for this?

10. Female armadillos always give birth to four offspring of the same sex.How can you account for this?

11. If an adult has approximately 60 trillion cells and a newborn baby has about 2 trillion cells, what is the average number of times every cell in the newborn baby has to divide in order to produce an adult?

12. Which best describes an actively growing organism, an arithmetic progression or a geometric

††††† progression?Why?

13. A certain restaurant buys 1000 amber water tumblers.An average of one tumbler is broken every day and each broken tumbler is replaced by a new one made of clear glass.What is the shape of the survival curve of amber tumblers?

14. List all the factors you can think of that affect growth in humans.

15. Which human organs regenerate damaged portions most easily?Which human organs show the fewest degenerative changes in old age?

16. How do the two lists you prepared for question number 15 compare?What explanation can you give for this?

17. In reptiles and birds the fetus is basically masculine, and fetal estrogen hormones are necessary to induce the development of female characteristics. In mammals the reverse is true, the fetus is basically female, with fetal hormones acting to induce the development of male characteristics. Can you suggest a reason why the pattern that occurs in reptiles and birds would not work in mammals?

18. Oviparity, ovoviviparity, and viviparity:

(a)    How are oviparity, ovoviviparity, and viviparity different?

(b)    How does fetal development differ in the monotremes, marsupials, and placental mammals?

19. In what ways does the reproductive system contribute to the bodyís homeostasis?

20. What circulatory changes associated with birth provide the pressure changes necessary to close the foramen ovale?