1. Mitosis Chapter 10 Pages 240-253

2. Cell Growth or Cell Division Personal growth—when you grow, what happens to your cells? Grow or Divide? The larger a cell becomes, the more demands the cell places on its DNA. In addition, the cell has more trouble moving enough nutrients and wastes across the cell membrane. Cell must divide to accomplish necessary tasks. Mitosis Video

3. Cell Division Cell division—process by which a cell divides into two “daughter” cells Before cell division occurs, the cell copies all of its DNA. Two stages to cell division 1. Mitosis 2. Cytokinesis

4. Chromosomes Each chromosome is copied before cell division, so each chromosome consists of 2 “sister” chromatids During cell division sister chromatids separate Centromeres—hold sister chromatids together Human—46 chromosomes

5. Cell Cycle Cell cycle—during the cell cycle, a cell grows, prepares for division and divides to form two daughter cells, each of which then begins the cycle again. Interphase—time between cell divisions It is a period of cell growth

6. Mitosis—four phases 1. Prophase—longest phase of mitosis – Chromosomes condense – Nuclear envelope dissolves 2. Metaphase—chromosomes line up across the middle Microtubules connect to the centromeres

7. Mitosis cont. 3. Anaphase—centromeres split allowing the sister chromatids to separate and become individual chromosomes 4. Telophase—chromosomes disperse – Nuclear envelope reforms around each cluster of chromosomes

8. Cytokinesis Cytokinesis—division of the cytoplasm Animal cells—the cell membrane is drawn inward until the cytoplasm is pinched in two Plant cells—cell plate forms midway between divided nuclei Video

9. Regulations to the Cell Cycle Proteins (cyclins) regulate timing Growth factors—stimulate growth and division of cells Uncontrolled cell growth – Cancer/tumors—do not respond to signals from proteins

10. Picture Credits http://www.gcarlson.com/images/new_cell_division.jpg http://www.karlloren.com/biopsy/images/mitosis.jpg http://www.learner.org/channel/courses/biology/images/archive/fullsize/1940_fs.jpg http://www.galaxynet.com/~corvid/cel/images/celi_cell_cycle.gif http://www.phschool.com/science/biology_place/labbench/lab3/images/prophase.gif http://www.uic.edu/classes/bios/bios100/labs/metaphase.jpg http://faculty.southwest.tn.edu/jiwilliams/Anaphase.gif http://www.agintheclass.com/CellBiology/images/CellBio/Lesson2/telophase.gif http://www.indigo.com/software/gphpcd/em21.jpg http://www.bio.txstate.edu/~dlemke/botany/1410lab/lab_exercises/lab3/cell_cycle/cytokines is.jpg http://www.bio.txstate.edu/~dlemke/botany/1410lab/lab_exercises/lab3/cell_cycle/cytokines is.jpg http://www.genomenewsnetwork.org/gnn_images/news_content/11_03/ovarian_cancer/ova rian-cancer-cell-color.jpg http://www.genomenewsnetwork.org/gnn_images/news_content/11_03/ovarian_cancer/ova rian-cancer-cell-color.jpg http://www.txtwriter.com/backgrounders/Cancer/figure1.jpg http://botit.botany.wisc.edu/images/130/Mitosis/Allium_Root_Prep._Slides/Prophase.low.jp g http://botit.botany.wisc.edu/images/130/Mitosis/Allium_Root_Prep._Slides/Prophase.low.jp g http://botit.botany.wisc.edu/images/130/Mitosis/Allium_Root_Prep._Slides/telophase_cytoki nesis.low.jpg http://botit.botany.wisc.edu/images/130/Mitosis/Allium_Root_Prep._Slides/telophase_cytoki nesis.low.jpg http://www.lima.ohio-state.edu/biology/images/metaphase.jpg http://www.freethought-forum.com/images/anatomy4/mitosis.gif