1. GHS Science CAPT Embedded Task Review
Lab Investigation: Enzymes

2. Your Task
A CT apple juice company needs your help to determine how enzymes can be used to produce apple juice from apple sauce.
They provide you with two enzymes to see which enzyme will make the most juice.
Enzymes:
Pectinase
Cellulase

3. What are Enzymes? This picture shows an enzyme binding to a substrate.
Enzymes are proteins found in the cells of all living things.
Enzymes connect to molecules in living things to break them apart or put them together.
A substrate is the original molecule that connects to the enzyme.
This picture shows an enzyme binding to a substrate.

4. Most GHS students used a procedure that looked something like this:
Lab Design
Most GHS students used a procedure that looked something like this:
1. Place filter paper in a funnel and put funnel in a flask.
Funnel with filter paper in it
Flask

5. Lab Design
2. Set up three flasks with funnels.
A B C

6. Lab Design 3. Pour exactly 20 g of apple sauce into each funnel.
A B C

7. Lab Design 4. Add a different enzyme to each funnel. 8 ml of Pectinase
8 ml of Cellulase
No enzyme added
A B C

8. Lab Design
5. Let each flask sit for exactly 10 minutes.
A B C

9. Lab Design
6. After 10 minutes, measure how much juice was produced from each flask using a graduated cylinder.
Graduated Cylinder
Apple Juice Produced
Apple Juice Produced
Apple Juice Produced
A B C

10. Sample Data Enzyme(s) Flask A Pectinase Flask B Cellulase Flask C
No Enzyme Added
Amount of
Juice Produced
3.0 ml
5.0 ml
0.5 ml

11. Analysis Questions
Directions: On a separate sheet of paper, answer the following questions in complete sentences.
Identify the following for this experiment:
Problem statement
Independent variable
Dependent variable

12. Definitions
Problem Statement: The problem that the scientist is trying to solve. Hypothesis: An educated guess that answers the problem statement. Often, an “If… Then…” statement is used. So, If I change the independent variable, Then the dependent variable will change in this way. Independent Variable: The variable in an experiment that the scientist purposefully changes. This change should affect the dependent variable. Dependent Variable: The variable in an experiment that changes and that the scientist measures. This variable depends on the independent variable. Control: The “baseline” that you can compare the other groups exposed to the independent variable against. Used test how valid the independent variable is. Controlled Experiment: An experiment in which all factors are kept constant except for the independent variable.

13. Analysis Questions
Identify two variables that were held constant in this experiment.
Explain why it is important to hold these variables constant.
What was the substrate and the product(s) in this experiment?
Why was it important that “flask C” was used?
Based on the data, what would your conclusion be for this experiment?

14. What are Enzymes? This picture shows an enzyme binding to a substrate.
Enzymes are proteins found in the cells of all living things.
Enzymes connect to molecules in living things to break them apart or put them together.
A substrate is the original molecule that connects to the enzyme.
This picture shows an enzyme binding to a substrate.

15. Going Further… Challenge Questions, Set 1
After performing this experiment, you learn from the apple juice company that Pectinase and Cellulase cost different amounts:
Pectinase: $.50 per ml
Cellulase: $1.00 per ml
The apple juice company wants you to be as cost-effective as possible in producing the most amount of juice.
Explain to the company which enzyme is most cost-effective (ml/$)?

16. Going Further… Challenge Questions, Set 2
A group of students are convinced that pectinase is the most cost-effective enzyme to choose to produce apple juice for the company. They think that temperature may affect how much juice pectinase can produce. In a new experiment, they test their hypothesis. Using the same basic design as the original experiment, the students heat apple sauce with pectinase to different temperatures to see which temperature is optimal for producing the most apple juice. The temperatures are: 0°C, 20°C, 40°C, 60°C, 80°C

17. Going Further… Challenge Questions, Set 2
The results of the students’ new experiment are shown below:
5 ml ml
Amount of Apple Juice Produced
Degrees Celcius

18. Going Further… Challenge Questions, Set 2
Explain the behavior of pectinase in temperature range 0-20 °C.
Explain the behavior of pectinase in temperature range °C.
What would be an appropriate conclusion for the new experiment?