Potato Catalase Lab Report
AP Biology, A2
15 September, 2015
Measure the activity of catalase in potato extract using several different methods.
a) Cut 20 small circles from a large filter paper disk using a hole puncher. Clean and dry several medicine cups and pour hydrogen peroxide into one. Put the catalase enzyme, previously prepared by blending a potato, into another medicine cup. Make a 1/8 dilution of the catalase by adding chilled distilled water. Use tweezers to grab one of the small filter paper circles, dip it into the enzyme solution, blot on a clean paper towel and place it on the bottom of the medicine cup containing the hydrogen peroxide. Once you put the circle down, start the timer. Once the circle comes to the top of the cup, stop the timer and record time. Repeat the above procedure for another 2 circles and record the time for them. Now pour a half of the remaining catalase into a new medicine cup and heat it in the microwave. Repeat the above procedure 3 times using the heated enzyme to dip circles into and record data. Finally take the rest of the original catalase and add a drop of hydrochloric acid to it. Repeat the above procedure 3 times using the acidified enzyme to dip the circles into and record data.
b) Take a test tube and place a …show more content…
The first method was soaking filter paper in catalase and observing how long it would take for the filter paper to float to the top of a beaker full of H2O2. Enzyme was changed every time – regular, heated or acidified. The second method was measuring the change in pressure during the reaction. This method involved using regular enzyme and then chilled enzyme. The last method was measuring the amount of H2O2 as the reaction progressed; this demonstrated the disappearance of the