To test the effects of temperature on the activity of yeast
Make up a quantity of bread dough .Stir a yeast cake in water and methodically mix the yeast with the dough. Divide the dough into three equal parts and put in pans or jars. Label samples 1, 2, and 3. Place sample 1 in a refrigerator, sample 2 in a warm place, and, sample 3 in a hot place. After a few hours study each sample.