On Friday, October 9, 2015, our class tried to answer the question is yeast alive? We used six materials. We used brains, test tubes, yeast, sugar, balloons and water.
Next, we put just the water and yeast mixture in test tubes 3 and 4. They had a bubbly chocolate color. Five minutes later test tube 1 rose from 25 ml to 75 ml. Test tube 2 went from 50 ml to 100 ml. In test tube 3 the balloon filled a little. In test tube 4 the balloon was not filled at all. They had no sugar in those test tubes.
At the end of the experiment the balloons on the two test tubes with sugar filled with carbon dioxide.
Our class found out that yeast is alive because it moved, grew and breathed. I felt happy because I learned something new.
Written by Carter, Second Grade Scientist