Download Liver Enzyme Lab Name___________________________per___

Liver Enzyme Lab
Name___________________________per___date___
Introduction: There are many chemical reactions that occur inside cells that are important to
sustain life. Enzymes are a type of protein can help speed up these reactions. Each enzyme is
specific to one type of chemical reaction. The activity of enzymes can be affected by temperature,
the presence of certain chemicals, and many other factors. Today you will be testing the
effectiveness of enzymes under different conditions.
Materials: 9 test tubes, 2 beakers, test tube rack, hot plate, forceps, 10 mL graduated cylinder,
timer, hydrogen peroxide (H2O2), water, raw liver, ice
Procedures:
1. Set up a hot water bath by filling one of the beakers with 100 mL of water and placing it on
the hot plate. Turn the hot plate up to 6. Using forceps, place a small piece of liver in a test
tube, and cover the liver with water. Place the test tube with liver into the hot water bath and
let the liver sit in the hot water bath for 10 minutes.
2. Set up a cold water bath by placing 2-3 pieces of ice in another beaker and fill the beaker up
to 100 mL with water. Using forceps, place a small piece of liver in a test tube and cover the
liver with water. Place the test tube with liver into the cold water bath and let the liver sit in
the cold water bath for 10 minutes.
3. Label the remaining test tubes A-G.
4. Set up each test tube by adding the liquids indicated in the data chart. Don’t add any liver
yet.
5. Complete a hypothesis for each test tube.
6. Add a small piece of liver to test tube A. Record your observations for about 2 minutes. (at
least 2-3 observations and be specific!)
7. Repeat step six for test tubes B through E, making sure to record observations for each test
tube.
8. Carefully remove the test tube from the hot water bath (make sure the hot plate is off and
allow all the equipment to cool). Using the forceps again, carefully remove the piece of liver
and add it to test tube F. Record your observations.
9. Using the forceps, carefully remove the piece of liver from the cold water bath test tube and
add it to test tube G. Record your observations.
10. Use your observations to infer what happened to the function of the enzyme in each
reaction and write your inference in the data table.
11. Answer the Analysis Questions and complete the Conclusion.
Data:
Test
Tube
Contents
A
10 mL water
B
10 mL H2O2
Hypothesis
Observations
What do you think
happened to the
enzyme?
C
5 mL H2O2
5 mL water
D
5 mL H2O2
5 mL acid
E
5 mL H2O2
5 mL base
F
5 mL H2O2
5 mL water
heated liver
G
5 mL H2O2,
5 mL water
cooled liver
Analysis Questions:
1. How did you know when the enzyme was working?
2. What effect did the water have on enzyme function? How do you know?
3. What effect did acid have on enzyme function? How do you know?
4. What effect did base have on enzyme function? How do you know?
5. What effect did heat have on enzyme function? How do you know? Why do you think this
happened?
6. What effect did cold have on enzyme function? How do you know?
7. Why did you include test tube A in this experiment?
8. What was the independent variable in this experiment?
9. What was the dependent variable in this experiment?
Conclusion: