1. Mitosis Ch. 9.1-9.3

2. Objectives 1.Describe how cell reproduction contributes to repair and growth 2.Structure of a chromosome 3.Explain cell cycle 4.Understand mitosis and cytokinesis 5.Basics of cancer

3. Two Functions of Cells 1.Repair 2.Growth The outer layer of skin on your arm consists of dead cell. –Constantly replacing each other! Cells also key in reproduction... more on that later

4. An idea of where we’re at

5. The DNA Genetic material located in nucleus of cell Most of the time it exists as chromatin Chromatin: –Uncoiled DNA, not visible

6. Chromosomes Home of the DNA Cell prepares to divide Chromatin fibers condense and become… Chromosomes: –Condensed, visible threads of genetic material Yarn example Humans have 46 chromosomes

7. Chromosomes Home of the DNA Right before division, the cell duplicates all of it’s chromosomes Sister Chromatids: –Identical, joined copies of chromosomes Centromere: –Joining region of chromatids

9. Check Your Neighbor Quiz your neighbor on the terms we just learned.

10. The Cell Cycle Let's Look at 3 examples of cell division (9.1 activity)

11. The Cell Cycle All cells divide at different rates Interphase: –90% of cycle Three stages during interphase: –G1 –Synthesis –G2 Miotic Stage (10%)

12. Cell Cycle Stages of Interphase G1: –Cell grows Synthesis: –DNA duplicates G2: –Cell prepares to divide Cell Cycle Animation and Different Types of Cells That Divide (9.2)Cell Cycle Animation and Different Types of Cells That Divide (9.2)

13. Cell Cycle Video Clip

14. Check Your Neighbor Quiz your neighbor on the cell cycle….

16. Mitosis Mitosis: –Non-sexual means of cellular reproduction Four Stages: 1.Prophase 2.Metaphase 3.Anaphase 4.Telophase Cytokinesis Let’s use pipe cleaners to demonstrate the stages of mitosis. Draw them out after you make them.

17. Mitosis Prophase Nuclear envelope dissolves Spindle forms Chromosomes visible

18. Mitosis Metaphase Chromosomes line up along equator Spindles attach

19. Mitosis Anaphase Chromatids separate Pulled towards opposite ends of cell by spindles

20. Mitosis Telophase Chromatids uncoil Nuclear envelope re-forms

21. Cytokenesis Division of cytoplasm Two identical daughter cells Mitosis: Let's watch the real thing!

22. Hand Jive Prophase Metaphase AnaphaseTelophase

23. Mitosis Quiz When I pause the movie, you tell me what stage of Mitosis we are in.

24. Cancer Family or friends with cancer? Cancer: –Uncontrollable cell division –Faulty checkpoints Out of control cell reproduction produces tumors Benign tumor: –Abnormal mass of normal cells Malignant tumor: –Mass of cancer cells Metastasis: –Spreading of cancer cells Activity 9.4 More cancer animation

25. How a tumor is formed

26. Proto-oncogenes encourage cell division