1. The Cell Cycle

2. The Life Cycle of a Cell Cell Cycle = events from one cell division to the next

3. The Cell Cycle

4. Divided into two parts Interphase M phase

5. Interphase Three parts –G1 – cell growth –S – DNA synthesis –G2 – preparation for division

6. M Phase Two Parts –Mitosis – nuclear division –Cytokinesis – division of cytoplasm

7. Control of the Cell Cycle G1 Checkpoint – decision to divide –Some cells exit the cell cycle and go into G0 –Example: Nerve and muscle cells

8. G2 Checkpoint –Allows cell to begin mitosis

9. Mitosis Checkpoint – Allows cells to begin G1 again

10. CANCER Results from uncontrolled cell division The genes that code for the proteins that regulate the checkpoints are mutated

11. MITOSIS 4 Phases –Prophase –Metaphase –Anaphase –Telephase http://www.biology.arizona.edu/cell_bio/tut orials/cell_cycle/cells3.htmlhttp://www.biology.arizona.edu/cell_bio/tut orials/cell_cycle/cells3.html

12. Prophase –Chromatids appear –Nuclear membrane disappears –In animals, spindle appears –Centrioles move to opposite poles

13. Prophase

14. Metaphase Chromatids line up at equator

15. Metaphase

16. Anaphase –Centromeres divide –Chromatids more toward opposite poles

17. Anaphase

18. Telophase –Nuclear envelopes form –Chromosomes uncoil –Spindle dissolves –Cytokinesis begins

19. Telophase

20. Cytokinesis Division of the cytoplasm Forms cleavage furrow in animal cells Cells Alive Animation Cytokinesis Video

22. Online Tutorial About the Cell Cycle http://www.biology.arizona.edu/cell_bio/tut orials/cell_cycle/cells2.html