Kristen Clark
Biology 101 Lab Section 041
9/22/14
Brandon Stroup
Abstract Catalase is an enzyme found in every living organism and is essential for cells. This lab explores how catalase reacts to four different temperatures and how the concentration percentage of substrate affects its reaction rate. The performance of catalase is dependent on many factors, so the purpose of the lab was to find the ideal concentration and temperature for catalase. We hypothesized that catalase would have the fastest reaction at its preferred temperature and at the highest substrate concentration. The results revealed that catalase, in fact, did perform best at the warm temperature and had the …show more content…
Catalase is an important enzyme found in plant and animal cells that accelerates the process of converting hydrogen peroxide to water and oxygen. This enzyme is vital to all organisms as it defends cells from too much oxygen exposure. This is important because catalase is found in most aerobic cells and prevents the dangerous oxidizing effects of H2O2. “Detoxification of H2O2 prevents fatal CO2 bubbles from forming in the blood” (Levina et al., 2014). “Although catalase is one of the most effective enzymes, the performance level could decrease or even be denaturized (destroyed) in certain conditions. Factors such as temperature, enzyme concentration, and pH of the enzyme solution can disable the effects of catalase” (Shikama & Yamazaki, 1961). We performed an experiment to record the reaction rates of different concentration percentages of substrate (enzyme reactant) in various temperatures to see what conditions catalase is most effective. We hypothesized that the higher substrate concentration and the closer to the preferred temperature of catalase, the higher the reaction rate will be. Our null hypothesis is substrate concentration and temperature will have no effect on catalase’s reaction …show more content…
The journals results can be supported with Table 1 and Figure 1 and relates back to the hypothesis pertaining to increased concentration of substrate results in increased reaction. Since the enzymes from the catalase convert substrates to O2, substrate concentration and enzyme concentration go hand-and-hand. The more substrate the concentration has, the more reaction will occur with the enzymes. The results for temperature in the lab we performed were similar to the journal, Changes in the Activity of Catalase in Relation to the Dormancy of Grapevine Buds. It states, “Low temperature was reported to decrease catalase activity in cucumber seedlings and in peach flower buts, in which also increased but break” (Nir, Shulman, Franberstein, & Lavee, 1986) which relates to Table 2 and Figure 2 since the reaction changes are relatively lower compared to room temperature and 40 degrees Celsius. Although low temperatures can negatively catalase, higher temperatures can also disable its performance. “Increasing the temperature beyond a certain threshold will denature the enzyme. Denaturation occurs when the hydrogen bonds and other weak interactions that determine enzyme secondary and tertiary structure are broken.” The data from the experiment