Vernier Software & Technology

# Enzyme Action: Testing Catalase Activity

## Introduction

Many organisms can decompose hydrogen peroxide (H2O2) enzymatically. Enzymes are globular proteins, responsible for most of the chemical activities of living organisms. They act as catalysts, substances that speed up chemical reactions without being destroyed or altered during the process. Enzymes are extremely efficient and may be used over and over again. One enzyme may catalyze thousands of reactions every second. Both the temperature and the pH at which enzymes function are extremely important. Most organisms have a preferred temperature range in which they survive, and their enzymes most likely function best within that temperature range. If the environment of the enzyme is too acidic or too basic, the enzyme may irreversibly denature, or unravel, until it no longer has the shape necessary for proper functioning.

H2O2 is toxic to most living organisms. Many organisms are capable of enzymatically destroying the H2O2 before it can do much damage. H2O2 can be converted to oxygen and water, as follows:

${\text{2 }}{{\text{H}}_{\text{2}}}{{\text{O}}_{\text{2}}} \to {\text{2 }}{{\text{H}}_{\text{2}}}{\text{O }} + {\text{ }}{{\text{O}}_{\text{2}}}$

Although this reaction occurs spontaneously, the enzyme catalase increases the rate considerably. Catalase is found in most living organisms. A great deal can be learned about enzymes by studying the rates of enzyme-catalyzed reactions.

## Objectives

In this experiment, you will

• Use an Oxygen Gas Sensor to measure the production of oxygen gas as hydrogen peroxide is destroyed by the enzyme catalase or peroxidase at various enzyme concentrations.
• Measure and compare the initial rates of reaction for this enzyme when different concentrations of enzyme react with H2O2.
• Measure the production of oxygen gas as hydrogen peroxide is destroyed by the enzyme catalase or peroxidase at various temperatures.
• Measure and compare the initial rates of reaction for the enzyme at each temperature.
• Measure the production of oxygen gas as hydrogen peroxide is destroyed by the enzyme catalase or peroxidase at various pH values.
• Measure and compare the initial rates of reaction for the enzyme at each pH value.

## Sensors and Equipment

This experiment features the following Vernier sensors and equipment.

### Option 2

You may also need an interface and software for data collection. What do I need for data collection?

## Agricultural Science with Vernier

See other experiments from the lab book.

 1 Introduction to Data Collection 2 Acids and Bases 3 Diffusion through Membranes 4 Conducting Solutions 5 Osmosis 6 Respiration of Sugars by Yeast 7 Reflection and Absorption of Light 8 Soil pH 9 Soil Salinity 10 Soil Temperature 11 Soil Moisture 12A Photosynthesis and Respiration (CO2) 12B Photosynthesis and Respiration (O2) 12C Photosynthesis and Respiration (CO2 and O2) 13 Transpiration 14A Cell Respiration (CO2) 14B Cell Respiration (O2) 14C Cell Respiration (CO2 and O2) 15 The Greenhouse Effect 16 Energy in Food 17A Enzyme Action: Testing Catalase Activity 17B Enzyme Action: Testing Catalase Activity 18A Lactase Action 18B Lactase Action 19 Oxygen Gas and Human Respiration 20 Biochemical Oxygen Demand 21 Animal Temperature 22 Lemon "Juice" 23 Ohm's Law 24 Energy Content of Fuels 25 Photovoltaic Cells 26 Wind Power 27 Watershed Testing 28 Interdependence of Plants and Animals 29 Biodiversity and Ecosystems

### Experiment 17A from Agricultural Science with Vernier Lab Book

#### Included in the Lab Book

Vernier lab books include word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.