1. DO NOW

2. Comparing Mitosis and Meiosis
SWBAT: Compare and contrast mitosis and meiosis in terms of the number of chromosomes in the resulting cells, and its effect on genetic variation.
EQ: How does the sorting and recombination of genes result in genetic variation?

3. Definition Meiosis Mitosis
Nuclear division to create gametes (sex cells)
Nuclear division that divides somatic (body) cells

4. Function Meiosis Mitosis Growth
Repair
Development
Produce gametes in sexually reproductive organisms

5. Type of Reproduction Meiosis Mitosis Sexual reproduction – Asexual-
Two parents
Offspring are genetically unique
Asexual-
One parent
daughter cells are genetically identical

6. Occurs in what type of Cell
Meiosis
Mitosis
Gametes (sex cells)
Somatic cells (body cells)

7. Genetically Identical?
Mitosis
Meiosis
genetically unique to parent
Due to crossing over and independent assortment
genetically identical to parent

8. Crossing-over? Chromosomes intertwine and swap pieces
Meiosis
Mitosis
Crossing over occurs during prophase I
Crossing-over does not occur

9. Pairing of Homologous Chromosomes pair during Meiosis I (prophase I)
Mitosis
Chromosomes pair during Meiosis I (prophase I)
Do not pair

10. Rounds of division Two rounds of division One round of division
Meiosis
Mitosis
Two rounds of division
One round of division

11. # of daughter cells and chromosomes
Meiosis
Mitosis
2 diploid cells
(2 sets of DNA)
46 chromosomes
4 haploid cells
(1 set of DNA)
23 chromosomes

12. Stages Involved Interphase Interphase I Meiosis I Prophase Metaphase
Mitosis
Interphase I
Meiosis I
Prophase I
Metaphase I
Anaphase I
Telophase I
Meiosis II
Prophase II
Metaphase II
Anaphase II
Telophase II
Interphase
Prophase
Metaphase
Anaphase
Telophase
Each round of division ends with cytokinesis!

13. Cytokinesis occurs and produces…
Meiosis
Mitosis
Two rounds
create 4 haploid gametes
One round
create 2 diploid somatic cells

14. Cytokinesis is involved
Ends with 2 cells that have 46 chromosomes
Homologous pairs separate first
Makes somatic cells
Makes gametes
Starts with one cell
Ends cells are identical to the original cell
Starts with interphase
Sister chromatids separate first
Produces haploid cells
DNA is replicated
Cytokinesis is involved
Produces diploid cells
Ends with 4 cells
Ends with 2 cells
Ends with 2 cells that have 23 chromosomes

15. Comparing Mitosis and Meiosis: Pencil Talk
Collaborate WITHOUT Writing:
Place your writing utensil in the cup on your desk.
Discuss the answers to the questions on the comparing mitosis and meiosis handout.
Individually Answer WITHOUT Talking
When time is up, you may pick up your writing utensil and complete the handout.

16. Meiosis vs. Mitosis

17. Mitosis and meiosis are processes involved in cellular reproduction
Mitosis and meiosis are processes involved in cellular reproduction. Which of the following describes and event that results from mitosis but NOT meiosis?
A. two stages of cell division
B. replication of cellular genetic material
C. daughter cells that are identical to the parent cell
D. four daughter cells that are produced from each parent cell

18. Which type of reproduction leads to increased genetic variation on a population?
A. Parthenogenesis
B. asexual reproduction
C. Sexual reproduction
D. Vegetative reproduction

20. The diagram shows homologous chromosomes during prophase I of meiosis
The diagram shows homologous chromosomes during prophase I of meiosis. Which of the following correctly describes the process being illustrated? 
A. mutation in which the DNA content of the gene is altered
B. segregation of sister chromatids
C. condensation and segregation of alleles
D. crossing-over in which alleles are exchanged

21. The diagram shows a cellular process that occurs in organisms
The diagram shows a cellular process that occurs in organisms. What is the name of this process? 
A. meiosis
B. mitosis
C. endocytosis
D. phagocytosis