3. (AKA--Mitotic Phase)

5. Period of cell growth and development that precedes mitosis and follows CYTOKINESIS (cell splitting) Longest phase of the cell cycle INTERPHASE:

6. 1.G 1 = Growth 1—most cell growth 2.S = Synthesis—cell makes a copy of its DNA 3.G 2 = Growth 2—cell grow a little to prepare for division

8. Period of cell growth and development that precedes mitosis and follows CYTOKINESIS (cell splitting) Longest phase of the cell cycle INTERPHASE:

9. 1. PROPHASE: Chromatin condense and thicken – now called chromosome. The nuclear envelope breaks down Centrioles move to opposite "poles“ (or ends) of the cell

10. 1.The spindle (centriole) fully develops 2.The chromosomes align at the metaphase plate (middle) 2. METAPHASE:

11. 1.Paired chromosomes separate and begin moving to opposite ends (poles) of the cell. 2.Spindle fibers lengthen and elongate the cell. 3.Each pole contains a complete compilation of chromosomes. 3. ANAPHASE:

12. 1.Nucleus begins to form at opposite poles. 2.The nuclear envelopes and nucleoli also reappear. 4. TELOPHASE:

14. CYTOKINESIS: = the division of the original cell's cytoplasm. (There are now two separate cells)

15. Animal Cell Cleavage furrow forms and pinches cell in half. http://wps.aw.com/bc_campbell_concepts_5/30/7910/2025031.cw/index.html Cytokinesis: Animal Cell vs. Plant cell

16. Plant Cell Cell plate forms to divide the cell. http://wps.aw.com/bc_campbell_concepts_5/30/7910/2025031.cw/index.html

17. CELL CYCLE 1.Interphase 2.Cell Division (Mitosis + Cytokinesis) MITOSIS 1.Prophase 2.Metaphase 3.Anaphase 4.Telophase

19. http://www.hybridmedicalanimation.com/anim_mitosis.html

20. Cell Cycle Regulation  Cell growth and division are carefully controlled.  Not all cells will go through the cell cycle at the same rate. Examples of cells rapidly dividing: Examples of cells NOT dividing often: RBC Muscle cells Skin cells http://stearn.ca/blog/wp-content/uploads /2009/05/red-blood-cells.bmp http://www.caring4cancer.com/uploadedImages/Website-C4C-20/Skin _Cancer_(Non-Meloma)/The_Basics/Epidermis-dermis.jpg Bone marrow http://www.rush.edu/rumc/images/ei_0062.gif Digestive tract cells http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book= cooper&part=A1967&rendertype=figure&id=A1982 http://apps.uwhealth.org/adam/graphics/images/en/19917.jpg Nerve cells http://activebodyreadymind.com/images/Nerve.jpg

21. Cell Cycle Regulation continued...  Cells that do not need to grow and divide can enter G 0 (resting) until they are needed.

22. Regulation  Cells have both internal and external regulators. Internal regulators—are called cyclin and make sure the cell is ready at certain checkpoints... If not, stops the cycle (see diagram) Is the cell big enough? Has all of the DNA duplicated completely or properly? Is the cell big enough? Are all of the chromosomes attached to spindle fibers and properly aligned on the metaphase plate?

23. Density-dependent inhibition External regulators— are called growth factors. If cells are touching other cells = no growth If space with no neighboring cells = grow/divide Regulation continued... http://media.pearsoncmg.com/bc/bc_campbell_concepts_5/media/art/ch8/ir/imagelib_tab_1/33.htm

24. What happens if cells LOSE the ability to CONTROL the cell cycle? http://www.yourcancertoday.com/ContentResources/Image/growth.jpg

25. Cancer  Cancer = uncontrolled cell growth... cancer cells do NOT respond to regulator signals... results in masses of cells called tumors... cancer = a disease of the cell cycle http://www.youtube.com/watch?v=LEpTTolebqo&feature=related