Caffeine Experiment Lab Report

The graph displays a negatively skewed trend, which suggests that the hypothesis was not supported. This is because the greatest percentage of caffeine (100%) did not result in the greatest reaction time, as predicted. The subjects who drank a 50% caffeinated beverage had the fastest reaction rate, taking an average of 0.39478 seconds to react. Comparatively, the subjects that drank the 100% caffeinated beverage had a slower average reaction time of 0.45917 seconds, taking longer to react. The subjects who were not exposed to any caffeine (0%) had a reaction time of 0.47293 seconds. There was no obvious trend for an increased reaction time with increased percentage of caffeinated beverage consumed. This is because the trial group who drank the 50% caffeinated beverage had, on average, faster reaction rates than the trial group who drank the 100% caffeinated beverage.

These results oppose the theoretical action of caffeine, which inhibits the action of adenosine by blocking its receptors to increase neural activity. As caffeine acts as a competitive inhibitor to block adenosine from binding, an increase in the concentration of caffeine molecules should result in an increase in the number of adenosine receptors which are blocked by caffeine. Thus, fewer adenosine molecules should be able to bind and so a decrease in its effects; drowsiness, fatigue and mental alertness, is expected to occur. Thus, it is expected that the subjects who drank 100% caffeinated beverages experience faster reaction times than those who drank the 50% caffeinated