1. Bellwork – Monday 9/23
During which phase of the cell cycle does DNA replicate?
Why does the DNA have to replicate before cell division?
How many daughter cells are produced from mitosis?
How do the cells at the end of mitosis compare the cells at the beginning of mitosis?
If a salamander tail cell has 24 chromosomes, how many chromosomes should the cell have after mitosis?
When in the cell cycle does cytokinesis begin?
Label the parts of the chromosome in the
Diagram.

2. Wednesday bellwork
The graph at left shows the cell cycle of a liver cell. How long does the cell cycle of a liver cell take
Which phase of the cell cycle does the cell spend the most time in?
List 3 things that happen in interphase
If a liver cell has 46 chromosomes before mitosis how many should it have after mitosis?

3. Bellwork:
Draw Interphase and Prophase. Describe the difference between these 2 phases
Draw a chromosome and label the centromere and chromatids
A cell normally has 36 chromosomes, how many will it have after mitosis
What are the new cells from mitosis called
List the phases of mitosis in order
What divides in mitosis?
What divides in cytokinesis?

5. After the quiz
In the green book, read the article on Cancer research on p. 340 then answer the following questions
Describe Cobb’s experiment on Cancer cells.
What was her independent and dependent variable
Describe how Levy was working to understand cancer.
What were her independent and dependent variables?

6. Bellwork 9/26 When does the cell’s nucleus divide into 2 new nuclei?
When are 2 new daughter cells formed?
Why do single celled organisms have cell division?
Why do multicelluar organisms undergo cell division?
What processes happen during the cell cycle?
During which phase of mitosis do you first see chromosomes? See 2 nuclei with visible chromosomes?
You are looking at a cell and the genetic material looks like a tangled ball of string, what is it called? What phase is it?

7. Meiosis EQ: How do cells divide for sexual reproduction
Sc.7.L.16.3 – compare mitosis and meiosis

8. What is sexual Reproduction?
A type of reproduction in which the genetic material from 2 different cells combine to produce offspring
Sex cells – the cells that combine in sexual reproduction – sperm and egg. (also called gametes)

9. What is chromosome number?
Chromosome number – every organism has a set number of chromosomes
In fruit flies there are 8 chromosomes
In humans there are 46 chromosomes

10. What are homologous chromosomes?
Homologous chromosomes are pairs of chromosomes found in body cells that are the same size and carry the genes for the same trait

12. How do sex cells and body cells differ?
Formed by mitosis
Are called diploid because they contain both homologous chromosomes
They have both of the homologous chromosomes
Produced by asexual reproduction
In a human they have 46 chromomes
In a fruit fly = 8 chromosomes

13. How do sex cells differ from body cells
Formed by meiosis
Are called hapliod because they have half the homologous chromosomes –
only 1 chromosome from each homologous pair
Formed by sexual reproduction
In a human they have 23 chromosomes
In a fruit fly they contain 4 chromosomes

14. Fruit flies have 8 chromosomes in each body cell diploid
They have 4 chromosomes in each sex cell
haploid

15. Why do organisms need sex cells?
When the 2 cells combine in sexual reproduction they get ½ of there chromosomes from each parent organism making a complete set.

16. How are sex cells made
Body cells are formed by mitosis, sex cells are formed by meiosis
Meiosis - a type of cell division that produces sex cells such as egg and sperm

17. chromosome number of different organisms.
How many chromosomes would be in a sex cell from these organisms? How many chromosomes would be in a body cell from these organisms?

18. The cell shown is a body cell. Draw a sex cell for the same organism

19. What are the stages of meiosis?
Meiosis involves 2 divisions of the cytoplasm called Meiosis 1 and Meiosis 2

20. Turn and talk
Name some ways that meiosis is different from mitosis

21. Parts of Meiosis Meiosis 1
Chromosome number decreases as homologous pairs separate
Meiosis 2
Chromatids separate and move to opposite ends of the cells

22. Meiosis coloring foldable:
Directions:
Label all key structures (homologous chromosomes, centromere, nuclear membrane, nucleus- ). 2 points
Label Meiosis I and Meiosis II at the top of the pages 1 point
Write a brief description of each phase– use the handout or the link from the website 8 points
Color each chromosome. Choose 2 different colors:
Color one homologous pair of chromosomes dark ________________ and light __________________. Choose the same color.
Color the other homologous pair of chromosomes dark ________________ and light __________________. Choose the same color, but different from step a.
DON’T forget to color your chromosomes accurately throughout all of the phases (4 points)

23. Meiosis Interphase
The chromosomes have replicated, and the chromatin begins to condense.

24. Meiosis Prophase I

25. Meiosis Metaphase I

26. Meiosis Anaphase I

27. Meiosis Telophase I & Cytokinesis

28. Meiosis Prophase II

29. Meiosis Metaphase II

30. Meiosis Anaphase II

31. Telophase II & Cytokinesis

33. Bellwork: are the following characteristics of mitosis, meiosis or both – create a Venn Diagram
Produces 2 identical cells
Produces haploid cells
Used for growth and repair
Produces 4 cells
Produces diploid cells
Chromosomes line up in the middle of the cell
Used for creation of gametes
Homologous pairs line up
Contains prophase, metaphase, anaphase and telophase (PMAT)

34. Meiosis Meiosis animation:
Mitosis animation
Meiosis square dance
Beginning of third class

35. Mitosis vs. Meiosis

36. How do mitosis and meiosis differ?
During mitosis and cell division, a body cell and its nucleus divide once and produce two identical diploid cells.
The two daughter cells produced by mitosis and cell division have the same genetic information.

37. How do mitosis and meiosis differ?
During meiosis, a reproductive cell and its nucleus divide twice and produce four cells—two pairs of identical haploid cells.
Meiosis forms sex cells used for sexual reproduction.

38. How does meiosis compare to mitosis
Characteristic
Mitosis
Meiosis
Function – type of cell produced
Number of nuclear divisions
Total Number of cells produced
Number of chromosomes in cells (haploid or diploid)
In a human cell there are 46 chromosomes. How many would be in a cell after…..
How does meiosis compare to mitosis