The Effect of Caffeine and Ethanol on the BPM of Daphnia magna

Abstract

Daphnia magna are known to have hearts that are comparable to human hearts. The Daphnia are used to test the effect of different substances on their heart rate to see a similar effect that would be in the human heart. We hypothesized that the addition of caffeine to the Daphnia would cause an increase in their beats per minute, while the addition of  ethanol would cause a decrease in the beats per minute of the Daphnia. The experiment consisted of five trials for each solution. Our data suggests that caffeine caused a significant increase in their heart rate (p=0.005024), and that ethanol caused a significant decrease in the heart rate of the Daphnia (p=0.028729). The results can be used to determine the effect ethanol and caffeine would have on humans.