Different Concentrations of Caffeine Affecting the Heart Rate of Daphnia

Abstract

            Caffeine occurs naturally in many plants, therefore it is also found in many food products, and many humans consume some form of caffeine everyday. For this reason many studies have been conducted on caffeine and how it affects the humans body. Some studies use Daphnia to test the effects of caffeine because the Daphnia's heart is similar to a humans and are easy to use for lab use. We predicted that by adding different concentrations of caffeine to the Daphnias environment we would speed up the heart rate in beats per minute (BPM) of the Daphnia. We conducted four trials per each concentration of caffeine finding the percent change in the Daphnia heart rate. Based on our results we found that there was not a significant difference between the two concentrations; however, we found that caffeine did have an overall increase in heart rate, this may be helpful to know for those who have a higher BPM that might want to avoid increasing it further.