BIOLOGY – 8TH Grade – Milton Lab Practice 1 - Measurement
INTRODUCTION Catalase is an enzyme normally found in many plant and animal tissues. Catalase breaks down toxic substances. It will convert hydrogen peroxide into oxygen and water. In this experiment, you will use potatoes as a source of catalase and determine the effect of temperature on the reaction of catalase with hydrogen peroxide.
MATERIALS: The following materials must be brought per group, not individually. 2 small potatoes 1 plastic bag (grocery bag) Paper towel 1 pair of Latex gloves per member of the group 500 ml Hydrogen Peroxide 1 Ruler 1 Permanent Marker 6 Sticky Labels
PROCEDURE 1 • • • • • •
Slice a potato into small squares about 4 or 5 millimeters on each side. Potatoes have the enzyme catalase. Make a mark about 5 centimeters from the bottom of a large test tube. Add potato squares to just below the line. Add hydrogen peroxide until is about even with the line. Make a mark about 5 centimeters from the bottom of a large test tube. Add potato squares to just below the line. Add hydrogen peroxide until is about even with the line.
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http://www.okc.cc.ok.us/biologylabs/Documents/Measurement/Measurement.htm
PROCEDURE 2 • • • • •
Fill a large glass with hot water between 40-45 degrees C. Pour about 5 mL of hydrogen peroxide in a large test tube. Place the tube in the water for 3 minutes. Next prepare another test tube with potato squares just as before. Add the warm hydrogen peroxide to the test tube with the potato squares and measure the bubbles of oxygen after one minute. Repeat the procedure with ice water. Record your results.
QUESTIONNAIRE: To be answered and published in your personal wiki. 1. What is the nature of the Hydrogen Peroxide compound? 2. What living things use this compound? And, what do they use it for? 3. What are the industrial uses or applications of Hydrogen Peroxide?
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http://www.okc.cc.ok.us/biologylabs/Documents/Measurement/Measurement.htm