Catalase Enzyme Activity
Enzyme Catalysis Lab
Teacher’s Guide
Table of Contents
Teacher Guide
Unit
Overview
Lesson Plan
Materials and Preparation
At least 1 day in Advance:
Morning of Lab:
Immediately Prior:
Variations and Extensions
Sample/Key
Hindsight
Student Guide
Objective
Standards
Introduction
Laboratory Sheet
Safety Precautions
Lab Team Materials
Shared Class Materials
Procedure
Student Lab Sheet
Catalase Enzyme Activity
Created by Cheryl Fiello, Linda Moule, Marizka Rivette, Sarah Tonks, and Eric Tucker for the UCLA TIIP Grant
Page 1
Spring 2012
Catalase Enzyme Activity
Teacher Guide
Unit
This lab fits in Chapter 2 (Chemistry of Life) of Freshman Biology with enzyme activity.
Overview
In this lab, students will use yeast as a source of catalase. Students will change the temperature of the substrate, hydrogen peroxide, and measure oxygen production with a gas pressure sensor. As oxygen is produced, gas pressure will increase.
Lesson Plan
This lesson can be completed between 1-4 days, but the full four days are recommended.
Day 1: Introduce enzymes to students (maybe lecture for 15-20 minutes only). Read through the student lab guide with the students.
Day 2: Conduct the lab.
Day 3: Debrief lab results and help students complete the lab graphic organizer
Materials and Preparation
Materials for each group bucket:
1 Lab handout (laminated)
1 LabQuest (fully charged)
1 Gas pressure sensor
Plastic tubing with 2 Leur locks and 1 small black stopper attached
1 Thermometer
1 10ml graduated cylinder
1 Test tube rack
3 18x150mm test tubes
3 Labeled pipets (water, yeast, H2O2)
1 Bottle hydrogen peroxide
4 Styrofoam cups
Advance Preparation
At least 1 day in Advance:
● This lab is pretty easy to set up, but you do need to test it before the students.
● Set up all the group lab materials in baskets for each group (see the Laboratory Sheet for a list of materials).
Created by Cheryl Fiello, Linda Moule, Marizka Rivette, Sarah Tonks, and Eric Tucker for the UCLA TIIP Grant
Page 2
Spring 2012
Catalase Enzyme Activity
The gas pressure sensor boxes have extra materials that are needed for other labs.
Please
DO NOT LOOSE THE PARTS NEEDED FOR OTHER LABS!
You will need:
■ The short tubing
● The length of plastic tubing connecting the rubber stopper assemblies to each gas pressure sensor must be the same for all groups. It is best to keep the length of tubing reasonably small to keep the volume of gas in the test tube low. If pressure changes during data collection are too small, you may need to decrease the total gas volume in the system. Shortening the length of tubing used will help to decrease the volume. For this reason, shorter tubing is provided (DO NOT CUT
THE TUBING—IT IS NEEDED FOR OTHER EXPERIMENTS!)
■ The two Luer locks (small beige screw on connectors) must be attached to both end of the short tubing. PLEASE DO NOT LOOSE THESE LOCKS!
■ The black stopper
■ All other materials (clamps, big stopper, syringe, etc.) can stay in the box.
Please do not give them to the students because they will play with them and loose them.
IMPORTANT NOTES:
○ You must use fresh hydrogen peroxide and yeast every year for this lab to yield decent results. Yeast can be bought at any grocery store (look at the expiration date closely) and hydrogen peroxide can be bought at any pharmacy. If peroxide is kept in the refrigerator, it must be brought to room temperature before the lab.
Set out several large beakers of water so the water equilibrates to room temperature overnight. You must run a trial of this lab to make sure that the yeast suspension is at the right concentration/activity (it will vary depending on the age and quality of the yeast).
To make yeast suspension, add the following into a Styrofoam cup (
Make a fresh suspension each period just before the passing period.
):
■ 100 ml warm water (37-40C, but no hotter or the yeast will die or enzymes will denature).
■ 1 packet of yeast (approx 7g)
■ 1 packet of sugar (the little
