Vernier Software & Technology

# Photosynthesis and Respiration (O2)

## Introduction

Plants make sugar, storing the energy of the sun into chemical energy, by the process of photosynthesis. When they require energy, they can tap the stored energy in sugar by a process called cellular respiration.

The process of photosynthesis involves the use of light energy to convert carbon dioxide and water into sugar, oxygen, and other organic compounds. This process is often summarized by the following reaction:

${\text{6 }}{{\text{H}}_{\text{2}}}{\text{O }} + {\text{ 6 C}}{{\text{O}}_{\text{2}}} + {\text{ light energy}} \to {{\text{C}}_{\text{6}}}{{\text{H}}_{{\text{12}}}}{{\text{O}}_{\text{6}}} + {\text{ 6 }}{{\text{O}}_{\text{2}}}$

Cellular respiration refers to the process of converting the chemical energy of organic molecules into a form immediately usable by organisms. Glucose may be oxidized completely if sufficient oxygen is available by the following equation:

${{\text{C}}_{\text{6}}}{{\text{H}}_{{\text{12}}}}{{\text{O}}_{\text{6}}} + {\text{ 6 }}{{\text{O}}_{\text{2}}} \to {\text{6 }}{{\text{H}}_{\text{2}}}{\text{O }} + {\text{ 6 C}}{{\text{O}}_{\text{2}}} + {\text{ energy}}$

All organisms, including plants and animals, oxidize glucose for energy. Often, this energy is used to convert ADP and phosphate into ATP.

## Objectives

In this experiment, you will

• Use an O2 Gas Sensor to measure the amount of oxygen gas consumed or produced by a plant during respiration and photosynthesis.
• Determine the rate of respiration and photosynthesis of a plant.

## 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 12B 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.