Enzyme Action: Testing Catalase Activity

Enzyme Action: Testing Catalase Activity

Introduction
In living organisms, enzymes control almost all of the chemical reactions that take place. They help to make the reaction occur faster, otherwise known as a catalyst. A catalyst is a substance that speeds up chemical reactions without being destroyed or altered during the process (Phifer 2010). If these enzymes weren’t present in our bodies it would take a very long to time to complete activities such as digestion. One of the main functions of these enzymes is converting the H202 in our bodies, produced by cellular respiration, into oxygen and water (David C. Whitcomb 2006).
In this experiment we measured the rate of enzyme activity, under various conditions, such as concentration, pH values, and temperatures using an O2 Gas Sensor (Phifer 2010). We can track the levels of gas in a closed chamber with the Gas Sensor. The more Hydrogen Peroxide destroyed, the higher percent of Oxygen will be on the chart.

Materials and Methods
In the first test, we placed three test tubes in a rack and labeled them 1, 2, and 3, filling each with 10 mL of 1.5% H2O2. Next, we started the enzyme reaction by mixing the test tube contents with 5 drops of enzyme suspension using a dropper pipette. We mixed this using the swirling flask. The next is to pour the contents into a 250-mL Nalgene bottle. Then, we placed the Gas Sensor into the top of the bottle and collected the data for 3 minutes. After that we repeated these steps with the next two test tubes, adding to the second one 10 drops of the enzyme suspension, and 20 drops to the third. With all the compiled data on the computer from the Gas Sensor, we created a graph and found the slope or rate of change for each reaction and then recorded it in tables 1 and 2 (Phifer 2010).
The second test will show how temperature effects the activity of enzymes. Specifically, our group was assigned to test the enzymes in a 50-55°C water bath with the test tubes placed in it....