1. Joseph H. Gault February 5, 2011 Central Catholic High School

2.  Electromagnetic radiation  The wavelength is shorter than that of visible light  The shorter wavelength has greater energy  The sun produces UV light  Responsible for sunburn and some cancers  Alters and damages DNA

3.  Can cause many problems in people, including heat exhaustion, heat stroke, heat cramps, heat rash, etc  These conditions can be cured in a number of ways: ◦ Hydration ◦ Loose Clothing ◦ Skin ointment  Vitamin E

4.  Antioxidant  Protects skin from UV damage  Minimizes cell damage from free radicals  May protect the heart in lower doses  Found in leafy green vegetables, olives, and various nuts and seeds

5.  Eukaryotic microorganism  Unicellular  3–4 µm diameter  Used in baking and production of alcoholic beverages  The most studied cellular model in research  Cell cycle is similar to human cells  Comparable DNA replication, recombination, cell division and metabolism

6.  The purpose of this experiment was to determine if the antioxidant Vitamin E can increase the survivorship of heat and UV stressed yeast cells.

7.  The vitamin E concentrations will not significantly affect UV-stressed and heat stressed yeast survivorship.

8.  Test tubes  Test tube rack  Micropipettes  Pipette tips  Yeast  (Saccharomyces  cerevisiae)  YEPD Agar Plates  YEPD Media (0.5% yeast,  2% Glucose, 2% Peptone)  Vitamin E  UV Lamp/hood  Proper safety equipment  Water  Spreader bar  Vortex  SDF  UV Safety Glasses  Thermometer  Water  Hot Plates  Beakers

9. 1. Saccharomyces cerevisiae was grown overnight in sterilized YEPD media. 2. A sample of the overnight cultures was added to fresh media in a sterile sidearm flask. 3. The culture of yeast was incubated at 30°C until a density of 50 Klett spectrophotometer units was reached. This represents a cell density of approximately 10 7 cells per mL. 4. The culture was diluted in sterile dilution fluid to a concentration of approximately 10 5 cells per mL.

10. 5. The following tubes were created: 6. 0.1 mL of each suspension was plated onto YEPD agar plates (54 total plates). 7. The plates were exposed to UV light for the following time intervals: a.0 Seconds b.30 Seconds c.60 SecondsYeastSDF Vit E 0 % Vit E0.01 mL9.99 mL0 mL 0.1% Vit E0.01 mL9.989mL0.1 mL 1% Vit E0.01mL8.99 mL1.0 mL

11. 8. Equivalent tubes were submerged in water baths for fifteen minutes at the following temperatures: a.32°C b.42°C c.52°C 9. 0.1mL of each suspension was plated onto YEPD agar plates (54 total plates) 10. Plates were incubated at room temperature for 48 hours 11. Colonies were counted. Each colony was assumed to have arisen from one cell.

12. 10 2 cells10 3 cells/mL 10 5 cells/mL 10 7 cells/mL (yeast) 100 uL Dilution Procedure

13. 0 % 0 Sec30 Sec60 Sec Trial 18528 Trial 29024 Trial 3902725 Trial 48723 Trial 5822927 Trial 6892622

14. .1 % 0 Sec30 Sec60 Sec Trial 1804020 Trial 2844227 Trial 3825040 Trial 4824342 Trial 5872838 Trial 6864736

15. 1 % 0 Sec30 Sec60 Sec Trial 1866445 Trial 2826747 Trial 3906449 Trial 4926043 Trial 5874842 Trial 6866248

16. 0 % 32°42°52° Trial 1764532 Trial 2844730 Trial 3794628 Trial 4834224 Trial 5824936 Trial 6774037

17. .1 % 32°42°52° Trial 1755648 Trial 2786447 Trial 3736849 Trial 4866353 Trial 5796546 Trial 6846742

18. 1% 32°42°52° Trial 1807756 Trial 2787554 Trial 3807359 Trial 4827957 Trial 5777258 Trial 6838160

19. P-Value: 4.78*10 -09 P-Value:.097 P-Value: 5.67*10 -17

20. P-Value: 1.40*10 -12 P-Value: 3.07*10 -12 P-Value: 0.884

21.  There was no significant variance in survival of the control groups treated with vitamin E.  There was a significant variation in survivorship of cells exposed to UV and not treated with vitamin E.  There was significant variation in survivorship of cells exposed to heat and not treated with vitamin E.  There was significant variation in survivorship of cells when exposed to the various temperatures and treated with vitamin E.

22.  The ANOVA indicated significant variation in the survivorship of the yeast colonies.  Therefore, the null hypothesis was rejected.  Vitamin E significantly affects yeast survivorship when exposed to heat and UV stress.

23.  Lag time  Use different concentrations of Vitamin E  Use different types of antioxidants (Lycopene, Vitamin A, Vitamin C)  Expose to varying amounts of UV light  Expose to a wider range of temperatures  Increase sample size

24.  "Differential Response to UV Stress and DNA Damage during the Yeast Replicative Life Span - Kale - 1998 - Developmental Genetics." Wiley Online Library. Web. 25 Jan. 2011..  "Heat Stress." Welcome To Web.princeton.edu. Web. 29 Jan. 2011..  "Safety and Health Topics: Heat Stress." Occupational Safety and Health Administration - Home. Web. 25 Jan. 2011..  "Vitamin E: MedlinePlus Medical Encyclopedia." National Library of Medicine - National Institutes of Health. Web. 25 Jan. 2011..  "Vitamin E." Office of Dietary Supplements (ODS). Web. 25 Jan. 2011..  "Vitamin E." Wikipedia, the Free Encyclopedia. Web. 25 Jan. 2011..  Web. 29 Jan. 2011..  "WHFoods: Vitamin E." The World's Healthiest Foods. Web. 29 Jan. 2011..