1. Agenda HW Review Quiz Trade and Grade Notes Class Practice
Independent Practice (with candy if you are good )

2. Review Point #1
In order for an organism to grow, it must make more somatic (body) cells.

3. Start with one skin cell
Key Point #1
The process of making more body cells is called MITOSIS. In mitosis one parent cell divides into two identical daughter cells.
Start with one skin cell
End with TWO skin cells that are just like the original one
*daughter doesn’t have anything to do with girl or boy, it is just the term used to talk about the child cell.
Mitosis happens

4. Pause- important questions to think about!
Why does mitosis happen in your body? (what is the point!)
Why is it important that you start with one cell but end with two?
Why would your body want to make make two IDENTICAL cells?

5. Key Point #2
The life cycle of a cell has two parts: Interphase and Cell Division. The cell spends most of its life in interphase.
Cell division
(mitosis)
Interphase

6. Interphase nucleus centriole DNA (chromatin) nuclear envelope 11/02/116

7. Interphase- In between divisions
Human cell during interphase
The cell grows.
The cell DOUBLES its DNA so it is ready to divide.
The cell replicates its centrioles.
46 chromosomes
1 and 2 are must know, 3 is just fyi
Human cell at the end of interphase
92 chromosomes, ready to divide!

8. Key Point #3
Once the cell has doubled its DNA, it is ready to divide in a process called mitosis.
Think of mitosis like baking a cake. It is a process with many steps. The steps must happen in order or it will be a disasterrrrrrrr

9. Prophase Metaphase Anaphase Telophase Please Make Another Touchdown
Steps of mitosis
Prophase
Metaphase
Anaphase
Telophase
Please
Make
Another
Touchdown

10. Prophase DNA organizes into chromosomes The nucleus breaks down.
11/02/11
Prophase
DNA organizes into chromosomes
The nucleus breaks down.
The centrioles separate, and a spindle begins to form. 10

11. 11/02/11
Metaphase-Middle
The chromosomes line up across the middle of the cell.
Each chromosome is connected to a spindle fiber at its centromere.
Spindle 11

12. Metaphase Plant Cell Animal Cell
11/02/11
Metaphase
Plant Cell
Animal Cell
Photographs from:

13. 11/02/11
Anaphase- Apart
The chromosomes (X’s) separate into individual chromatids (v’s) and are moved apart to opposite sides of the cell. 13

14. Anaphase Plant Cell Animal Cell
11/02/11
Anaphase
Plant Cell
Animal Cell
Photographs from:

15. Telophase- Tear Two nuclei start to form.
11/02/11
Telophase- Tear
Two nuclei start to form.
The cell begins to tear apart.
Chromosomes lose their distinct shapes. 15

16. Telophase Plant Cell Animal Cell
11/02/11
Telophase
Plant Cell
Animal Cell
Photographs from:

17. Key Point #4
Once mitosis is over, cytokinesis happens. Cytokinesis = splitting of cytoplasm

18. Cytokinesis- Cut The cytoplasm and cell membrane are cut in half.
11/02/11
Cytokinesis- Cut
The cytoplasm and cell membrane are cut in half.
Two daughter cells are made with IDENTICAL DNA. 18

19. Cut your cards

20. Hold up the correct step of mitosis based on the description below
The nucleus begins to break apart

21. Hold up the correct step of mitosis based on the description below
Chromosomes move towards opposite sides of the cell

22. Hold up the correct step of mitosis based on the description below

23. Hold up the correct step of mitosis based on the description below
Chromosomes line up along the center of the cell

24. Hold up the correct step of mitosis based on the description below
Chromosomes are in a V shape

25. Hold up the correct step of mitosis based on the description below

26. Hold up the correct step of mitosis based on the description below

27. Hold up the correct step of mitosis based on the description below
Spindle fibers begin to form

28. Now you try!!! Pull apart your twizzler.
Twizzlers represent chromosomes.
When you think you have built the cell correctly, call Ms M over and she will initial the box.
If you do not have initials in all the boxes you will get a zero for classwork!

29. Examples

30. Examples

31. Examples

32. Examples

33. THE BOTTOM LINE Mitosis happens so an organism can GROW.
Mitosis makes TWO daughter cells with IDENTICAL DNA
Mitosis makes more SOMATIC (body) cells.