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The Effect of Uva

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Submitted By flame889
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The Effect of UVA, On the Growth of Saccharomyces Cerevisiae Protected By Sunscreen
For many years ultraviolet radiation has been studied. Man has found and created many uses for ultraviolet radiation, and has learned much about it. In the last few decades, the most researched aspect of ultraviolet radiation is its effect on humans, specifically melanoma. Contrary to recent belief, UVA, a low-energy wavelength of UVR emitted by the sun, was thought to be less dangerous than UVB, due to the obvious characteristic that it is a higher wavelength than UVA. UVA actually does do indirect DNA damage through the formation of free radicals in cells. Since most sunscreens do not protect against it, UVA is one of the reasons there are so many cases of melanoma in the world today. This project was designed to test a specific sunscreen that claimed it was protective against UVA, and test this sunscreen. Fifteen Petri-dishes of yeast were split up into groups of five, only two of the three groups being radiated, and only one group protected by sunscreen (for control purposes), was tested to see if the sunscreen was actually UVA protectant. An 18 in., UVA emitting black light was used to radiate the cultured yeast cells for 20 minutes. After a few days results were collected. There is no conclusion that can be made from the data because the data did not prove the hypothesis correct or incorrect. There were few problems with this experiment, mold grew on some of the plates, sunscreen and radiation was not evenly applied during the test, and the UVA light source was not very powerful. I would like to thank Bobby Scott and Amber Lindner for helping me with my

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