1. Why do cells divide? Genetically Programmed Cell volume gets too big External Stimulus Dividing bacteria

2. Cell division = One cell makes two cells Parent cell DNA replicates Two daughter cells are genetically identical to each other and to parent cell = clones

3. Chromatin = uncondensed DNA Chromosome = condensed DNA The same DNA can appear in two forms

4. 1 Chromosome 1 chromatid per chromosome 1 DNA double helix 1 Chromosome 2 chromatids per chromosome 2 DNA double helices DNA replication

5. Cell division in eukaryotic cells: Karyokinesis = division of the nucleus Cytokinesis = division of the cytoplasm

6. Interphase 1.DNA called chromatin 2.DNA replicates 3.Cell does normal activities 4.Not a phase of mitosis

7. DNA = Chromatin Interphase nucleus

8. Interphase Chromatin in nucleus

9. Mitosis 1.Prophase 2.Metaphase 3.Anaphase 4.Telophase Know this page

10. Prophase Nuclear membrane disappears Nucleolus disappears Chromatin condenses into chromosomes Spindle fibers appear

11. Chromatin Chromosomes

12. Metaphase Chromosomes line up in center of cell

13. Chromatids (DNA double helix) Two chromatids per chromosome Centromere = holds chromatids together

14. Anaphase = Sister chromatids separate from each other

15. Telophase Cytokinesis makes 2 new cells Chromosomes decondense into chromatin Nucleolus reappears Nuclear membrane reappears

16. Early Telophase Late Telophase

17. Animal cell membranes pinches together between two new cells Plant cell wall grows between two new cells Cytokinesis

18. Plant Cytokinesis = division of cytoplasm Interphase Telophase Anaphase Metaphase Telophase Prophase

19. http://www.unm.edu/~asmund/mitosis.jpg Interphase Animal cytokinesis = pinching of plasma membrane Late Telophase Early telophase Anaphase ProphaseMetaphase

20. http://images.google.com/imgres?imgurl=www.cll.wayne.edu/isp/mrichmon/Mitosis.gif&imgrefurl=http://www.cll.wayne.edu/isp/mrichmon/mitosis.htm&h=3 65&w=366&prev=/images%3Fq%3Dmitosis%26start%3D20%26svnum%3D10%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26sa%3DN Plant or Animal cell mitosis? Plant

21. Telomeres = break off and lead to cell death and aging. Telomeres Telomerase Enzyme prevents loss of telomeres Found in 95% of Cancer cells Makes cells immortal Cancer drug = telomerase inhibitor