In this lab our goal was to test the reaction time of yeast catalase in hot and cold temperatures and in the level of PH solution. Yeast catalase is an enzyme that can be found in yeast cells. An enzyme is substance produced by a living organism that acts as a catalyst to bring about biochemical reactions. Yeast catalase breaks down hydrogen peroxide into hydrogen and oxygen. In this lab, generally, we were trying to figure out the reaction time of yeast catalase in different temperatures and different solutions of hydrogen peroxide. We also were testing the boyancy of the yeast balls. We made little spheres out of yeast and calcium alginate. When the yeast interacts with sodium alginate it becomes a gooy liquid because the bonds are not strong,