Modeling Meiosis I

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Biology I
Name______________________
Meiosis
Date _____________Pd ____
Objective: To model Meiosis I
Prelab Questions: Answer before proceeding.
1. The purpose of meiosis is:
2. Define the following terms:
a. gamete-
b. haploid number-
c. homologous chromosomes
d. synapsis-
e. crossing overProcedure/ Analysis:
1. You have been given 20 playing cards (10 red/black), representing homologous
chromosomes. Match up the homologous pairs.
2. Arrange cards the pairs as they would be in prophase I.
3. Describe what would be happening now between homologous chromosomes? Use
correct terminology.
5. Now model anaphase I. (do it randomly between red and black cards)
6. Is the genetic material in each forming nucleus identical? Explain.
7. Count the # of black cards in each forming nucleus. Record. Do the same for the red
cards.
Nucleus 1
Nucleus 2
# Black _________
#Black _________
# Red __________
#Red __________
8. Let black represent the paternal chromosomes and red the maternal. Describe the
chromosomal mix from the parents in each new nucleus. Do both nuclei contain the
same parental mix? Explain.
9. After telophase I, how many chromosomes does each new cell have? How does it
compare to the parent cell? Are they single or replicated chromosomes.
10. Are these two cells formed identical? Explain.
11. Will the two cells formed from each of these two in meiosis II be identical? Explain.
12. How is anaphase II different than anaphase I?
13. Which set of divisions (meiosis I or II) is most like mitosis? Explain.
14. Explain how this process results in such a mix of genetic material. Even if a couple
has 20 children (no identical twins), none would be genetically identical.
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