1. Section 9-2 : Mitosis & Cytokinesis

2. Essential Questions What are the events of each stage of mitosis? What is the process of cytokinesis?

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

5. The process of asexual reproduction begins after a sperm fertilizes an egg.

6. Skin cancer - the abnormal growth of skin cells - most often develops on skin exposed to the sun. Cell that reproduce by asexual reproduction reproduce constantly.

7. Chromosomes Chromosomes are rod-shaped structures made of DNA and protein. Sister Chromatids are identical halves, attached at the center. (at the Centromere) Held together by the Centromere Centromere

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

9. 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

10. Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

11. Mitosis begins (cell begins to divide) Centrioles (or poles) appear and begin to move to opposite end of the cell. Spindle fibers form between the poles. Nuclear Membrane disintegrates Chromatin condenses Centrioles Sister chromatids Spindle fibers

12. Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Spindle fibers Centrioles

13. Metaphase “Middle” Chromosomes attach to spindle apparatus. Chromosomes align along equator of cell. (Line up in the middle)

14. Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

15. Anaphase Microtubules shorten, moving pairs of chromosomes to opposite poles. “Away” Centrioles Spindle fibers

16. Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

17. Telophase Chromosomes reach the poles Nuclear envelope reforms Chromosomes De-condense Two new nuclei form. Chromosomes appear as chromatin (threads rather than rods). Mitosis ends. Nuclei Chromatin

18. Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

19. Cytokinesis Animal cells : Cleavage furrow forms, pinches, and divides into 2 daughter cells Plant cells : Cell plate forms, divides daughter cells