The power was off last night, and the yeast cultures in your incubator cooled down from 25 degrees to 20 degrees centigrade in temperature. to your great relief, you find that the yeast cells did not die. however, when you analyze the composition of the lipids in the plasma membrane of your yeast cells, you discover

Two unique things would have likely happened. First there is a lower percentage of long chain fatty acid residues in the cells that were grown at 20 degrees than when the cells were grown at 25 degrees C, and also that there is a higher percentage of unsaturated fatty acid residues in the cells grown at 20 degrees than when the cells were grown at 25 degrees C