The Effect of Different Salinity Levels on Growth Rate of Tetrahymena thermophila


  • Christina Lee
  • Victoria Park
  • Ziyu Gan


Tetrahymena thermophila are single-celled organisms that are commonly used for research purposes due to their short doubling time. They are found in freshwater aquatic systems and are a food source for zooplankton, and juvenile salmons require zooplankton as their food source. The effect of different salt concentrations on the growth rate of the freshwater organism, T. thermophila were observed under different NaCl concentrations within the Biology department at the University of British Columbia. T. thermophila were exposed to four different salt concentration levels, 0%, 0.025%, 0.050%, and 0.100% over a 26-hour period. 100μL of samples were taken out every two hours during the first day to a total of eight hours, and the samples were taken out with a two-hour interval (24th and 26th hour of incubation) until the 26th hour was reached on the second day of the experiment. Considering that T. thermophila live in freshwater environments that contain little to no salt concentration, they grew best when exposed to 0.05% NaCl. Based on the results, T. thermophila were not affected by NaCl concentrations during the 26 hours of incubation.