Question

Please Refer to This Lab Background: Procedure Only one group prepares each type of extract, and then shares the extract. Make enough for all of the groups. Cut a piece of the tissue to be tested, approximately 4x4 cm. Cut into smaller pieces; then grind in a mortar and pestle with a pinch of sand and 8 mL of deionized water to break the cell walls and release the catalase into solution. Place the mortar and pestle on the side bench for other groups to use also. Be sure to wash the mortar, pestle and dropper well when finished, using soapy water. Keep all tissue material out of the sink drain. Discard any remaining tissue material in the trash. Use 1 drop (NOT 1 dropperful!) of the fluid extract in the following experiments. Activity 2 - Effect of temperature on catalase activity in potato HYPOTHESIS: Temperature has no effect on catalase activity. Add 1 drop of potato extract and 1 ml of water in each of four test tubes numbered 1A, 2A, 3A, and 4A. Add 1 mL of H2O2 to each of four test tubes numbered 1B, 2B, 3B, and 4B. Expose the tubes to the temperatures below for 5 minutes. Measure and record the temperature of each exposure. Tubes 1A and 1B: in a beaker of ice water Tubes 2A and 2B: at room temperature Tubes 3A and 3B: in a beaker of water at 70°C Tubes 4A and 4B: in a beaker of boiling water After 5 min, pour the peroxide from tubes 1B, 2B, 3B and 4B into corresponding tubes 1A, 2A, 3A and 4A. Measure the height of the foam layer in each tube after 1 minute. Record the results and answer the questions in your laboratory report. Wash all glassware with soapy water, rinse well and dry. Activity 3 - Effect of pH on catalase activity HYPOTHESIS: pH has no effect on catalase activity. To each of the tubes below add 1 drop of potato extract and 1 mL of buffer solution as indicated. Tube 1: pH 2 Tube 2: pH 3 Tube 3: pH 11 Add 1 mL of H2O2 to each tube and record the time. After 1 min, measure the height of the foam layer in millimeters (mm). Record the results and answer the questions in your laboratory report. Wash all glassware with soapy water, rinse well and dry.

Activity 2 - Effect of temperature on catalase activity in potato

2. Record the height in mm of the foam layer after 1 min.

Tube	Temperature (°C)	Thickness of Foam (mm)

4. Which temperature completely inactivated catalase?_______________________

Activity 3 - Effect of pH on catalase activity

Record Your Results:

2. Tube	pH	Thickness of Foam (mm)

4. At what pH is catalase completely inactivated?

Answer 1

The values were not given in the question, so I have given representative values, they are from original experiments. Answers are true in all the cases, irrespective of experiment.

• At 100 C the catalase is completely inactivated.
• At pH 2 the enzyme is completely inactivated.
• Find the data sheet attached below.

Table 1 Catalase activity (ml) Catalase activity (ml) Temperature (C) 4 0.1 4 25 2 2 70 1 0.01 100 100 Temperah 70 25 O Catalase activity (ml) Catalase activity PH (ml) 0.1 2 0.2 3 4 7 1 1 11 11 7 3 2 PH pH