Questions:

BACKGROUND
1. Meiosis reduces the chromosome number by __________ and results in the production
     of sex cells called __________ & ___________.

2. Summarize the process of:
      a) Meiosis I -->
      b) Meiosis II -->

PROPHASE I
3. Match the following terms to their description.
      a) synapsis                          L) types of germ cells
      b) tetrads                           M) a set of 4 chromosomes joined together
      c) diploid                            N) each member of a chromosome pair
      d) homologous                   O) has both chromosomes of each homologous pair
      e) primary spermatocyte      P) process by which homologous chromosomes pair
             & primary oocyte                  up during Prophase I of meiosis

4. When the chromosomes appear in Prophase I of meiosis, why do they appear as “X’s”?

METAPHASE I
5. Do the chromosomes line up along the equator as pairs (X) or as tetrads (X-X)?

ANAPHASE I
6. As the chromosomes are pulled apart in Anaphase I are the identical pairs or the
      homologous pairs of chromosomes being pulled apart?

TELOPHASE I
7. a) Are the two new (daughter) cells produced by Telophase I identical to each other?
    b) Are the two new (daughter) cells produced by Telophase I identical to the original
          primary spermatocyte (or primary oocyte)?

8. How does Telophase I differ in males and females?

METAPHASE II
9. How do the chromosomes line up along the equator differently in Metaphase II than they
      did in Metaphase I?

ANAPHASE II
10. As the chromosomes are pulled apart in Anaphase I are the identical pairs or the
       homologous pairs of chromosomes being pulled apart?

TELOPHASE II
11. How does Telophase II differ in males and females?

12. How does the final results of meiosis differ in males than in females?

13. How do the sperm and ovum (egg) differ from the primary spermatocyte and primary
       oocyte?

PART II : NONDISJUNCTION

14. Can a nondisjunction occur in either Meiosis I or Meiosis II or does it always occur in the           same one?                     EXPLAIN.

15. Briefly describe each of the following examples of nondisjunction.
        a) Down’s syndrome -->
        b) Klinefelters syndrome -->
        c) Turner’s syndrome -->

16. Recently scientists have discovered “supermales” with the genotype XYY, and
        “superfemales” with the genotype XXX. Are these sexual “disorders” also caused
        by nondisjunction?                     EXPLAIN.

      Meiosis allows for a reshuffling of chromosomes, resulting in variety in the sperm and
egg. These combinations result from the manner in which the chromosomes line up during Metaphase I. Because of these different arrangements, up to 4 different combinations are
possible in the sperm and egg produced from the original cell in Diagram #1. Use the 4
circles below to show these 4 possible combinations.

                Show each of the 4 possible combinations below by taping the cutouts
                used earlier in this lab into each of the appropriate circles below.

SHOW ME ___________	SHOW ME ___________
SHOW ME ___________	SHOW ME ___________