Methods in Scientific Inquiry

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The purpose of this experiment was to determine the effects that common food additive chemicals have on the heart rates of Daphnia magna, considering that there are health concerns for humans regarding numerous food additives. Various food additives that have different purposes were used, as was a control group. In order to conduct this experiment, solutions for each of these chemicals were created based on the concentrations found in processed food. Three Daphnia magna were exposed to each solution for 20, 25, and 30 minutes respectively, and the heart rate of each was recorded using a microscope. The hypothesis was that there would be no statistically significant difference between the heart rates of treated and untreated Daphnia magna, but that was disproven. The vast majority of the Daphnia magna had lower heart rates overall than their counterparts in the control group. Additionally, most of the Daphnia magna had heart rate patterns over time that differed from the control group, as well as different correlations with time.



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