Circadian rhythms are found in a variety of organisms and are involved in controlling activity of the organism. However, a circadian rhythm for yeast has not been discovered yet. The goal of this study is to find evidence for a circadian rhythm in yeast by looking for changes in GAPDH concentrations and peroxiredoxin levels. GAPDH and peroxiredoxin have been shown to be controlled by the circadian clock in many organisms. A continuous yeast culture is sampled every two hours over a period of about 104 hours. Each sample is processed and tested for the concentration of GAPDH using GAPDH reagent. Western blots will also be performed to determine peroxiredoxin levels