The effect of increasing glucose concentrations on the swimming speed of <i>Tetrahymena thermophila</i>

Abstract

Tetrahymena thermophila, a unicellular ciliate, is a good model organism for the study of cilia. This study investigates whether the concentration of glucose in the growth medium had an effect on the swimming speed of the organism. We treated T. thermophila with different glucose concentrations, 0.2%, 1%, 2% and 4%, and observed their behaviour and measured their swimming speed. We observed an increase in average speed in the treatments of 0.2% to 2% glucose concentration. We also found a decrease in speed when the concentration of glucose was 4%. One-way ANOVA gave a p-value of 1.12 x 10^-3. The increase in speed when glucose concentration increased from 0.2% to 2% may have been due to aerobic respiration, which upon generating ATP provides energy to power microtubules in the cilia to beat faster. The decrease in speed at 4% glucose concentration may have been due to oxygen depletion in the test tubes that resulted in T. thermophila producing less free energy.