By Courtney E., Nathy M., and Chahana P.
Is your skin really safe from the sun when you use sunscreen? Science Club for Girls Media Team did a full experiment to test the difference between using sunscreen and no sunscreen. In our experiment, we first began with a petri dish with a layer of Yeast-Extract Dextrose (YED), a gel-like substance that allows the yeast to grow. We then applied a UV-sensitive yeast strain on top of the gel evenly (the UV-sensitive yeast uses the YED to grow when exposed to sunlight). We decided to use UV-sensitive yeast because this particular strain has a similar structure to DNA; it repairs itself when exposed to UV radiation with sunscreen.
We marked the petri dish into four sections, each labeled with: Sun (no sunscreen), No sunscreen and sunlight, sunscreen type A, and sunscreen type B. We had one side labeled “no sunscreen and sunlight” because we wanted to see the effect of not wearing sunscreen versus having it on; we had this section covered with duct tape. The duct tape represented clothing or zero sunlight. The left sections were exposed to sunlight for about 20-30 minutes. After leaving the yeast alone for a week, the majority of the data confirms that the areas with sunscreen were more protected than the area with no sunscreen. The section that was covered with duct tape was able to grow yeast even though it was covered.
In conclusion, our skin needs sunscreen because it protects us. Not using sunscreen can make our cells unrepairable due to the UV-radiation damage. Next time you head for the beach, apply sunblock!