The Effects of Various Caffeine Concentrations on the Population Curve of Tetrahymena thermophila

Abstract

Due to the lack of literature on the effects of caffeine on humans, we aimed to further characterize its impact through this study. The experiment conducted investigates the impacts of varying caffeine concentrations on the population growth curve of the unicellular eukaryote, Tetrahymena thermophila. Through a series of experiments using stock caffeine concentrations of 10-2 ,10-3 ,10-4 M, the growth pattern of T. thermophila was monitored over 30 hours. We hypothesized that caffeine would influence the population curves of T. thermophila, either stimulating or hindering overall growth. Utilizing a hemocytometer for cell counting, growth rates were measured and various time points throughout the study. Results from the study were subjected to statistical analysis, using a one-way ANOVA TEST, yielding an F-statistic of 0.625793 and p-value of 0.60157. These results reveal no significant difference in growth curves among the caffeine concentrations and highlight the comparable variability between the four groups. However, observable trends were noted, including the overall decrease in population density of the organism for the four groups. Our study, like many others, includes several limitations including temperature variations, poor laboratory techniques, and variability in sampling. The statistical results of the experiments were inconclusive, suggesting further research to be carried out to address this study’s limitations.