Investigating Factors that Affect
the Rate of Enzyme Activity
See Textbook Pg 61.
Enzymes are very large complex organic molecules that are synthesized by the cell to perform specific functions. These biological catalysts are important because they speed up the rate of the reaction that would otherwise be too slow to support life. Catalase is an enzyme present in the cells of plants, animals and aerobic (O2 requiring) bacteria. It promotes the conversion of hydrogen peroxide, a powerful and potentially harmful oxidizing agent, to water and oxygen. Catalase also uses hydrogen peroxide to oxidize toxins including phenols, formic acid, formaldehyde and alcohols. Catalase is an example of a particularly efficient enzyme. Catalase has one of the highest turnover numbers for all known enzymes (40,000,000 molecules/s). This high rate shows an importance for the enzymes capability for detoxifying hydrogen peroxide and preventing the formation of carbon dioxide bubbles in the blood. This laboratory exercise involves the use of an enzyme that will react with hydrogen peroxide. The enzyme is catalase and hydrogen peroxide (H2O2) is the substrate. The reaction is as follows: catalase
2H2O2 2H2O + O2
Ingested hydrogen peroxide is a poison, while external use of this substance is not. However, the generation of oxygen gas requires careful handling due to the potential combustion hazard oxygen presents when handled near a: • heat source - open flame
• spark potential - static discharge
Wear safety goggles when pouring hydrogen peroxide.
In this investigation, you will design and conduct a controlled quantitative experiment to examine how different environmental conditions can affect catalase activity. During this lab all data...