Wednesday 1/11

1. Wednesday 1/11 1. Draw a rough sketch of the picture above, and label what the numbers 1-4 are • Agenda • Cell Specialization Activity • Mutations • If time, discuss biology of Fat

2. Discuss DNA Extraction Lab

3. Cell Specialization

4. Each of your cells contains ALL of your DNA…

5. How do you get different cells if they all contain the same DNA? • each cell only • Uses a small part of DNA instructions • Unneeded genes are “switched off” • Makes mRNA from part of code it needs • Makes proteins for that type of cell

6. Carousel Activity: Structure Matches Function • Go to each of the 7 stations • On your own sheet of paper • Include title of each station • Answer questions at each station IYOW. • FINAL QUESTION: Since each cell of your body has the same set of DNA, how can you make so many types of cells?

7. Ex: Muscle cells only make mRNA from “muscle DNA”

8. Muscle cells are very long & very thin • Each cell is as long as the muscle Muscle Cell

9. Structure Very long & thin Function To shorten Structure Matches Function Round cell can’t shorten Very long cell can really shorten

10. Ex: • Red blood cell makes mRNA from “blood cell DNA”

11. Structure • Biconcave disk • Function • Carry oxygen to cells • Structure Matches Function • In small capillaries RBCs must squeeze through • Helps release oxygen

12. Getting back to DNA, RNA, Protein… • Why is the sequence of Amino acids important? • http://www.youtube.com/watch?v=Pjt1Q2ZZVjA

13. In Your Notes Write the Amino Acid sequence if the RNA is: 1. UGG-CUA-UAC-AGC: Try - Leu – Tyr – Ser 2. UGG-CUA-CAC-AGC: Try - Leu – His – Ser 3. UGA-CUA-CAC-AGC: Stop – Leu – His – Ser 4. UGC-UAC-ACA-GC Cys – Tyr – Thr - ?

14. Mutations Changes in DNA that aren’t corrected Can be triggered by: Radiation (including sun) Toxins Viruses Spontaneous

15. May be harmful or may not make a real difference Mutations during mitosis can cause cancer

16. Cancer Starts with one mutated cell Cell division goes “out of control” Cell constantly divides

17. It takes 2 mutations in a single cell 1) in a Cell Division gene 2) in a Tumor Supressor gene One cell must accumulate 2 or more mutations So chances of cancer increase with age

18. Definitions: Tumor = cells with abnormal growth Malignant = tumor spreads & damages organs Benign = tumor doesn’t spread or harm (aka cyst or growth) Metastisize: tumor breaks, travels in blood, starts new tumors.

20. Treatments Chemotherapy, radiation therapy Target rapidly dividing cells Cancer cells, skin cells, hair follicles

21. Do you know any ways to prevent cancer? Don’t smoke. Maintain a healthy weight Exercise Eat a healthy diet! Protect yourself from the sun Practice safe sex Don’t drink too much alcohol

22. Antioxidants • These help protect your cells from the effects of free radicals • Free radicals= molecules produced when your body breaks down food or by environmental factors such as exposure to tobacco and radiation • Free Radicals can damage cells and lead to cancer

23. Antioxidants are found in fruits, vegetables, grains, nuts, poultry and fish

24. Video http://www.youtube.com/watch?v=Rfm6RJlasj4&feature=fvsr

25. The Biology of FAT • At age of about 5 or 6 • your body decides that amount of fat is “normal” (Set Point) • Your body works hard to maintain the Set Point • If you lose weight • Your fat cells shrink, but don’t go away • Strong hormones signal you to EAT to fill up fat cells • Liposuction • Seems like it should work, but it doesn’t • Remaining fat still works to keep set point • You end up weighing the same as before (or more) • With fat in different places • Only thing that can change Set Point • Exercise!