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Meiosis
1.
What process occurs before meiosis? Replication (copying the DNA)
2. How many divisions occur in meiosis? Is this the same as mitosis? Explain.
Two divisions- Meiosis I and Meiosis II. Mitosis only has one.
3. The original cell that divides by meiosis is ________________ or 2n.
4. How many daughter cells can be produced by meiosis? Is this the same as mitosis?
Explain. 4 daughter cells result from meiosis – Mitosis only result in 2.
5. What is the chromosome number of the daughter cells produced by meiosis?___ How
does this compare to the number of chromosomes in the original cell?
6. What are the daughter cells called that are produced by meiosis? Name them.
Gametes: ________, ________
7. Where does meiosis occur in males? Testes
8. Where does meiosis occur in females? Ovaries
9. In humans, how many chromosomes are in the original that undergoes meiosis? Are
they single or double stranded?
10. After one division, how many chromosomes are in the cells?
11. After the second division, how many chromosomes are in the cells?
12. Is meiosis sexual or asexual reproduction?
13. Are eggs & sperm haploid or diploid?
14. What process joins the egg & sperm to restore the original chromosome number of
the organism?
15. When a sperm fertilizes an egg, a new 2n cell forms called the
_____________________.
16. Homologous chromosomes (homologs) are pairs of sister chromatids that have the
same genes, but may have different alleles. (one from mom, one from dad)
17. _____________ reduces the chromosome number by half, while ____________
restores it.
18. In Meiosis I, what separates? Homologs – (the homologous chromosomes)
19. . In Meiosis II, what separates? Sister chromatids
21. Name these stages of Meiosis I. PMAT I
22. Name 1 things that occur in Early Prophase I. Chromosomes condense
23. What joins together in Late prophase I?
24. _______-_____ (below) is a key process in late prophase I.
26a. Crossing-over results in genetic ________________ in the offspring, which allows
for more _______________ within a species.
26b. Multiplying possible gamete types = assorting the genes independent of each other
(not always together)…Law of Independent assortment
27. What happens during Metaphase I? ___________ pairs align at equator
28. Name 1 thing that occurs in Anaphase I? Homologs ____________
29. Name 1 thing that occurs in Telophase I? Nuclear envelope reappears
30. At the beginning of Meiosis II, each cell has how many homologs of each
chromosome? ______– pairs of homologous chromosomes have seperated
31. The gametes at the end of Meiosis II will have how many copies of a gene for a
trait?
32. Name the stages in Meiosis II. PMAT II
33. What happens in Prophase II? Nuclear envelope fragments
34. Where are the sister chromatids in Metaphase II?
35. What happens to the sister chromatids during Anaphase II?
36. Meiosis results in __________ haploid cells called _________ that have _______
copy of each chromosome and _________ allele for each gene in different
___________________.
Comparing Mitosis & Meiosis
37. Complete the following table comparing mitosis & meiosis.
Mitosis
Number of divisions
Number of Daughter
cells
Genetically Identical
Chromosome Number
Where Occurs
When occurs
Role
Meiosis