1. Mitosis & Meiosis

2. MITOSIS (My-toe-sis)
The process of cell division which results in the production of two daughter cells from a single parent cell. 
The daughter cells are identical to one another and to the original parent cell.
Every different type cell in your body contains the same genes, but only some act to make the cells specialize – e.g. into nerve or muscle tissue.

3. MITOSIS
Through this process, a nucleus divides to form two identical NUCLEI.
Each new nuclei contains the same number and type of chromosomes.

4. Chromosomes
Play an important part in cell division, also called chromatin
Structures in the nucleus that contain DNA.
You have 46 of them in your cells (23 pairs). One came from mom and one from dad. The pairs are held together by a centromere.
Diagram:

5. Parent cell
Chromosomes are copied and double in number
Chromosomes now split
2 daughter cells identical to original

6. Stages of Mitosis Interphase Prophase Metaphase Anaphase Telophase
Cytokinesis

7. Stages of Mitosis 4. 1. 2. 3.

8. Interphase The cell prepares for division DNA is replicated
Organelles are replicated
Cells increase in size
Chromosomes appear as threadlike coils (chromatin)

9. Interphase
Animal Cell
Plant Cell

10. Prophase The cell prepares for nuclear division
Packages DNA into chromosomes
Each chromosome now exists as a pair of chromatids joined together by a centromere.
Centrioles (or poles) appear and begin to move to opposite ends of cell
Spindle fibers form between the poles
Nuclear membrane disappears

11. Prophase
Animal Cell
Plant Cell

12. Metaphase The cell prepares chromosomes for division
Chromatids (or pairs of chromosomes) attach to the spindle fibers
Chromosomes line up at the center of the cell.
Spindle fibers attach from daughter cells to chromosomes at the centromere.

13. Metaphase
Animal Cell
Plant Cell

14. Anaphase The chromosomes divide Spindle fibers pull chromosomes apart.
The centromeres split and the two chromatids of each double chromosome separate.
The chromatids of each pair are then dragged to the opposite ends of the cell

15. Anaphase
Animal Cell
Plant Cell

16. Telophase The cytoplasm divides
The group of chromatids assemble at opposite ends of the cell.
The spindle fibers disintegrate and a nuclear envelope forms around the chromosomes at each end.

17. Telophase
Animal Cell
Plant Cell

18. Cytokinesis Cell membrane/cell wall pinches in and forms two
daughter cells.

19. Plant Cell Mitosis—same process with a few twists!
Because plant cells have rigid cell walls, they do not pinch apart like animal cells do.
Instead, they form a structure called a cell plate, where a new cell wall will form.
Also, plant cells don’t have centrioles.

20. Mitosis Animation
Mitosis Animation
Brain Pop
Mitosis – BrainPOP
Cell Division

21. MEIOSIS (My-oh-sis)
Meiosis is the type of cell division by which germ cells (eggs and sperm) are produced.
One parent cell produces four daughter cells.
Daughter cells have half the number of chromosomes found in the original parent cell.

22. MEIOSIS
During meiosis, DNA replicates once, but the nucleus divides twice.

23. MEIOSIS First Division
Prophase I: Each chromosome duplicates and remains closely associated. These are called sister chromatids.
Metaphase I: Chromosomes align at the center of the cell.
Anaphase I: Chromosome pairs separate with sister chromatids remaining together.
Telophase I: Two daughter cells are formed with each daughter containing only one chromosome of the chromosome pair.

24. PROPHASE I
Prophase I: Each chromosome duplicates and remains closely associated. These are called sister chromatids.

25. METAPHASE I and ANAPHASE I
Metaphase I: Chromosomes align at the center of the cell.
Anaphase I: Chromosome pairs separate with sister chromatids remaining together.

26. TELOPHASE I
Telophase I: Two daughter cells are formed with each daughter containing only one chromosome of the chromosome pair.

27. MEIOSIS Second Division
Prophase II: DNA does not replicate.
Metaphase II: Chromosomes line up at the center of the cell
Anaphase II: Centromeres divide and sister chromatids move separately to each pole.
Telophase II: Cell division is complete.
Four haploid daughter cells are formed.

28. PROPHASE II
Prophase II: DNA does not replicate.

29. METAPHASE II and ANAPHASE II
Metaphase II: Chromosomes line up at the center of the cell
Anaphase II: Centromeres divide and sister chromatids move separately to each pole.

30. TELOPHASE II Telophase II: Cell division is complete.
Four haploid daughter cells are formed.

31. MEIOSIS ANIMATIONS AND REVIEW

32. Genetic information is identical
MITOSIS VS MEIOSIS
MITOSIS
MEIOSIS
Sexual Cell divides once Four haploid daughter cells Genetic information is different
Asexual
Cell divides once
Two daughter cells
Genetic information is identical