1. 1 1 Mitosis BODY Cell Division (Chapter 3 : 3 p.86-89)  Mitosis is the process in which the nucleus divides to form two new nuclei.  Mitosis differs in plants and animals.  A form of asexual reproduction – one cell divides into two

2. How do little elephants grow up to be BIG elephants?

3. Skin cancer - the abnormal growth of skin cells - most often develops on skin exposed to the sun.

5. Cells that reproduce by asexual reproduction reproduce constantly.

6. Animated Mitosis Cycle http://www.cellsalive.com/mitosis.htm Interphase Prophase Metaphase Anaphase Telophase & Cytokinesis

7. 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 CELL MEMBRANE Nucleus Cytoplasm

8. Animal Cell Plant Cell

9. Mitosis begins (cell begins to divide) Centrioles appear and begin to move to opposite end of the cell. Spindle fibers form between the centrioles. Centrioles Sister chromatids Spindle fibers

10. Animal Cell Plant Cell Spindle fibers Centrioles

11. Chromatids (or pairs of chromosomes held together by centromeres) meet in the middle of the cell and attach to the spindle fibers. Centrioles Spindle fibers

12. Animal Cell Plant Cell

13. The centromere splits and the sister chromatids (or pairs of chromosomes) separate and begin to move to opposite ends of the cell. The separated chromatids are now called chromosomes. Centrioles Spindle fibers

14. Animal Cell Plant Cell

15. A new nucleus forms around each identical groups of chromosomes at opposite sides of the cell and two new nuclei form. Chromosomes appear as chromatin (threads rather than rods). The cell membrane starts to move inward near the middle of the cell. Mitosis ends. Nuclei Chromatin

16. Animal Cell Plant Cell

17. The cytoplasm is completely pinched creating two identical daughter cells – each with its own nucleus with identical chromosomes.

18. Animal Mitosis -- Review Interphase 1. Prophase 2. Metaphase 3. Anaphase 4. Telophase Cytokinesis

19. Plant Mitosis -- Review Interphase 1. Prophase 2. Metaphase 3. Anaphase 4. Telophase Cytokinesis

21. Cell plate

22. I I nterphase P P rophase M M etaphase A A naphase T T elophase C C ytokinesis IPMATC I Pray M ore At T he Church

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24. 24 - Cell Division 24