1. Cell Division
Mitosis vs. Meiosis
….the battle continues

2. Mitosis Type = Asexual reproduction Growth, maintenance, and repair
Takes place in somatic (body) cells

4. Cell Cycle Interphase Cells are in interphase 90% of the time.
G1- growth
S - chromosome replication
G2- Prepare for mitosis
Mitosis (nuclear division)
Cytokinesis (cytoplasmic division)

5. Overview of Mitosis Mama Cell=2n (diploid) Daughter cell= 2n

6. Interphase (pre game show)
Chromosomes are copied (# doubles)
Chromosomes appear as threadlike coils (chromatin) at the start, but each chromosome and its copy(sister chromosome) change to sister chromatids at end of this phase

8. PROPHASE CENTRIOLES APPEAR AND MOVE TO OPPOSITE ENDS OF THE CELL
Spindle fibers form between centrioles

9. METAPHASE
Chromosomes “meet” in the middle. Spindle fibers attach to the centromere of each chromosome.

10. ANAPHASE
Sister chromatids separate from each other and are “pulled” to opposite ends of the cell.

11. Telophase
Cell plate forms and cell membrane begins pinching in= “cleavage.”
Chromosomes look like threads (chromatin) again. Nuclear envelope forms again.

12. Cytokinesis Division of the cytoplasm
Cell membrane completely pinches off.
Cycle starts again.

13. Rounds of Cell Division
One

14. Number of daughter cells
Two, each identical to each other and the parent.

15. Meiosis

16. Meiosis Type: Sexual Reproduction Purpose: To create haploid gametes
Takes place in gametes (sex cells/egg and sperm cells)

17. Meiosis Types of cells that undergo meiosis: Gametes (sex cells)
Egg and sperm

18. Meiosis: Overview Parent Cell: diploid= 2n After Meiosis I
After Meiosis II
Daughter Cells:Haploid= n ; and all genetically different from eachother and parent cell

19. ???
Why would it be important for the gametes to contain half as many chromosomes as a somatic cell?

21. Meiosis I
Prophase I: Crossing Over occurs to create genetic variability.

22. Meiosis I: Metaphase I
Homologous chromosomes line up in the middle different from mitosis!

23. Meiosis I: Anaphase I
Chromosomes pull apart

24. Meiosis I: Telophase I

25. Meiosis II
2nd round of division

26. Meiosis II: Prophase II
2 cells now
Centrioles appear and move to opposite ends

27. Meiosis II: Metaphase II
Chromosomes line up in the middle

28. Meiosis II: Anaphase II
Sister chromatids pull apart and move to opposite ends
DRAW IT YOURSELF

29. Telophase II

30. Chromosome number in Meiosis
Mother cell-2n (Diploid)
Daughter cells- n (Haploid)

31. Round of cell division Two
Illustrate mother cell with four chromosomes (2n) and daughter cells with two chromosomes (n) in each. Make sure to include replication before meiosis I.

32. Number of daughter cells
Four

34. Let’s compare!

35. Ticket to the Lab
Name 3 key differences between mitosis and meiosis on your foldable.