This week in AP Bio, we continued discussing catalase. In class on Monday and Tuesday we conducted an experiment to see how catalase would react with hydrogen peroxide. (2A) To start off our experiment, we created yeast balls with catalase in them to serve as yeast balls. We then dropped the yeast balls into the hydrogen peroxide individually and calculated the time it took for each ball to rise to the top once it hit the bottom. When catalase breaks down hydrogen peroxide, it breaks it down into its reactants. The substrates of hydrogen peroxide are water and oxygen gas. The oxygen gas is what makes the yeast balls rise to the top. My lab group, in particular, measured the rate of reaction for different concentrations of hydrogen peroxide. Our control was .6% and our experimental was .3%. We also tried to see how it would react if we increased the heat significantly, but the yeast balls never even touched the bottom of the beaker, so we could not measure the time it took to reach the top.
During our experiment, we made a conclusion that the higher the concentration of hydrogen peroxide, the faster the catalase reaction takes place. We believe this is due to the favt that more hydrogen peroxide molecules come into contact with the enzymes in the yeast balls and force the reaction to happen more quickly. Eventually, the velocity of the reaction reaches a maximum, meaning the enzymes cannot break down the hydrogen peroxide any faster than they already are. The enzyme concentration remains the same, but the hydrogen peroxide concentration increases at a constant rate. You can see this in the graph pictured above. When we reduced the amount of substrate and decreased the concentration of the hydrogen peroxide, the balls took significantly longer to rise.