The effect of temperature on the rate of food vacuole formation in Tetrahymena thermophila.

  • Milton Chan
  • Ashley Pinter
  • Ivneet Sohi


Phagocytosis and the formation of food vacuoles are essential processes involved in the growth and development of Tetrahymena thermophila populations. Temperature has an effect on both membrane fluidity and the rate of protein synthesis, which ultimately influence the efficiency of phagocytosis. We developed an experiment based on the nature of phagocytosis to investigate the effect of temperature on the rate of food vacuole formation in T. thermophila. In order to investigate this, samples of T. thermophila were placed in different temperature conditions and after two and five-hour acclimation periods were permitted to feed on yeast for one hour. The average number of food vacuoles formed was then counted in order to determine the rate of formation at each temperature. Our results suggest that the rate of food vacuole formation increases with both temperature and acclimation time. The rate of food vacuole formation after two hours of acclimation averaged between 5.6 and 11.5 vacuoles per hour as compared to 10.3 and 13.1 vacuoles per hour after five hours. Overall, it appears that both increasing temperature and environmental acclimation time contributes to an increase in the rate of food vacuole formation. The influence of temperature was not the same at the two acclimation-time conditions. Future research is required to confirm the effects observed as well as to provide appreciable insight into the mechanisms involved in these processes in T. thermophila.