PART C: Catalase Enzyme Action
READ OVER THE ENTIRE LAB PROCEDURE BEFORE STARTING:
In this section of the Lab Inquiry, you will use the PASCO pressure probe to observe the action of the enzyme Catalase in the conversion of hydrogen peroxide into oxygen and water. This is a key reaction in many living things to dispose of hydrogen peroxide. Catalase is a protein enzyme. Catalase is found in plant, especially in potatoes.
TECHNICAL NOTES : Catalase prep: 1 liver/100mL DI Water. FILTER with cheese cloth and dispense the liquid for the experiment. FRESH LIVER solution is needed daily. ( Alternate: 75 g potato in 100 mL water) Keep on ice .
1. Open the SPARKVue App
2. Turn on the SparkLink.
3. Connect the Low pressure probe ( alternate procedure : Connect a high pressure probe) into the front of the SparkLink. It requires an analogue adapter ( Or check the connections of the probe and all wires.)
DO not get the sensor wet and DO not let the low pressure probe get higher that 100 KPa.
4. On the computer, open the appropriate graph set up as instructed.
5. Check the hardware set up. Click on the hardware set up icon if the SparkLink picture is not already present.
Click on the SparkLink picture to identify the Low pressure probe. It may have appeared automatically.
6. Close the hardware set up.
7. Set up the data table and graph: a. The data table title and graph title , "Time vs. Pressure"
The first column would be Time ( s), second column Pressure (KPa) which is kiloPascals, and S.I. unit for pressure
Graph : Y= the tested variable , so this is Pressure. X = the independent variable, so Time
DO add a second Y-Axis to the graph for Temperature
8. Set up the Pressure Probe . CAUTION:The pressure can build up, never look directly down at the capped flask. The stopper can pop out. STOP the experiment if 500 KPa are reached.
A. Set up a 200- 300 mL SPECIAL thick-walled flask. Put a label on the flask with the group I.D., class period, and the chemical contents. You will need a stopper which fits the flask.
1. Attach it via a hose, connector and glass prong on the flask. ( Mr. Ulmer will check and assist.)
2. Trial TWO and THREE ONLY : Get a one hole stopper: Put the temperature probe through the one hole stopper. You will measure the temperature changes as well as the pressure changes. The pressure changes indicates the enzyme action. NOTE : The probe must contact the solution; you may need to add D.I. water to achieve this.
B. Trial ONE : Acquire 10 mL of Hydrogen Peroxide solution. Make a 10% solution . Put the 10 mL into a beaker and fill the beaker with D.I. Water, up to 100 mL . Pour The solution into the flask.
TRIAL ONE : WHEN READY to RECORD : Add the 2 mL of enzyme, catalase to the flask. Cap it. Record results ( Your table and Graph ) as TRIAL 1
Trial TW0 : 1. Use 10 mL hydrogen peroxide , fill to only 100 mL
2. Add 10 mL enzyme solution
Trial Three : 1. Use 10 mL of hydrogen peroxide( A solution with 10 mL of hydrogen peroxide in 100 mL of water)
Add water to your flask so that the temperature probe is contacted.
See the "Heating Option " below.
2. Add 25 mL of enzyme solution.
C. Acquire 25 mL of Catalase solution in a beaker. Do NOT add it to the flask until you are ready to begin. You should first be sure that all is ready. When you are ready to begin, add 25 mL of the enzyme , catalase into the flask . Cap the flask securely with the stopper. Twist the stopper into place, and begin recording. Set it up on a heater, but DO NOT plug it in yet.
9. Start recording on the computer (CHECK FOR new App). You should begin generating a graph and data. Take a picture of your set up. Email it to your Google account and add it to your lab folder.
Trial THREE Heating Option :
1. Begin Heating the solution after 30 seconds.
2. Heat on a medium setting. Record your setting.,and monitor your pressure. You will heat the solution until it is showing a significant change in enzyme action. Research the optimal temperature for catalase from chicken. What is the body temperature for a live chicken?
3. STOP HEATING if it begins to boil.
10. The experiment may run for 20 minutes. Monitor your graph to determine the ending point. If the line of the graph stops changing before 20 minutes, you may stop the recording. NOTE : Also stop the experiment if 500 KPa are reached. Caution :This is a high pressure. Release the tubing to relieve the pressure. Stop, save your data. Transfer it to the Lab Report folder in your shared Google folder.