Subject Area(s): Biology, Environmental Science, Botany
Associated Unit: N/A
Associated Lesson: N/A
Activity Title: Do Plants Sequester Carbon Dioxide?
PASCO GLX with CO2 sensor
Mint leaves
http://www.gardenality.com/images/plants/source/Chocolate-Mint-Plant.jpg
Copyright © PASCO
Grade Level: High School (9-12)
Activity Dependency: N/A
Time Required: 1.5 hours
Group Size: 2-4 students
Expendable Cost per Group: Less than $1.00
Summary
Students will become familiar with the carbon cycle and the role that photosynthesis plays in the
cycle. More importantly students will discover that plants actually remove CO2 from the
atmosphere and could help in decreasing the excessive amount of CO2. Students will see how
engineers are working to create synthetic trees to mimic the process of photosynthesis to remove
carbon emissions produced by manufacturing companies. Global warming will be a common
thread throughout the lesson.
Engineering Connection
Many engineers are concerned with the increasing amounts of carbon dioxide in the atmosphere.
Knowledge of the efficient process of photosynthesis makes engineers aware of how nature can
work to remove this greenhouse gas from the atmosphere. Engineers can then use this
information to create “plant-like” structures that will be just as efficient, if not more so, than
nature itself at sequestering carbon dioxide.
Engineering Category
(1) Relates science concept to engineering
Keywords
Photosynthesis, Carbon Cycle, GLX, CO2
Educational Standards
 Alabama Course of Study Objectives:
o Biology: 3, 10, 14
o Botany: 7, 12
o Environmental: 1, 2, 4, 9
 Alabama Course of Study Objectives:
o
Algebra: 2, 12
Pre-Requisite Knowledge
Students should have prior knowledge of the process of photosynthesis.
Learning Objectives
After this activity, students should be able to:
Compare the uptake of carbon dioxide by plants as it undergoes photosynthesis to a controlled
situation with no plants.
Relate how engineers use nature as an example to create new technologies
Materials List
Each group needs:
PASPORT Xplorer GLX
PASPORT CO2 GAS Sensor
Mint plant, small
Sampling Bottle (included with sensor)
Wet paper towel to wrap around roots of mint plant
Lamp
Heat Sink (bottle with water to be placed between the sampling bottle and light)
Introduction / Motivation
Students will conduct the Carbon Cycle Role Play as an introduction to the lab.
Vocabulary / Definitions
Word
Definition
Sequester
to remove or separate
Photosynthesis The process in green plants and certain other organisms by which
carbohydrates are synthesized from carbon dioxide and water using light as an
energy source
Global
An increase in the earth's average atmospheric temperature that causes
Warming
corresponding changes in climate and that may result from the greenhouse
effect
Greenhouse
Any of the gases whose absorption of solar radiation is responsible for the
Gas
greenhouse effect, including carbon dioxide, methane, ozone, and the
fluorocarbons
Procedure
Background
Carbon can be called the element of life. It plays a major role in all living organisms.
Because all of the Carbon that will ever be on Earth is already here, there must be a way for
the Carbon to be recycled. This process is called the Carbon Cycle. Carbon cycles through
the living and non-living parts of the earth in what is called a biogeochemical cycle. Carbon
combines with other elements to create compounds. The geologic part of the carbon cycle
includes carbon compounds found in rocks. These compounds remain trapped until
processes such as erosion and volcanic eruptions return carbon to the atmosphere in the form
of carbon dioxide. These processes may take millions of years. A faster movement of
carbon involves the biological carbon cycle.
All living things on earth depend upon producers in one way or another. Producers are
organisms that can make their own food, most often through the process of photosynthesis.
Photosynthesis occurs in the chloroplasts of autotrophs. Here, the energy from the sunlight
causes a chemical reaction which combines carbon dioxide and water into glucose and
oxygen. Glucose, a carbohydrate, is the main source of energy for living organisms.
Through the process of cellular respiration, the energy that is trapped in the chemical bonds
of glucose is released as glucose combines with oxygen to produce carbon dioxide and water.
These processes depend on the changing weather in an area. At times, it is too cold or too
dry for photosynthesis and respiration to continue to move carbon dioxide through the
atmosphere. At other times, the amount of carbon dioxide being cycled greatly increases.
There is also a long-term storage of carbon in organisms that died but did not decompose.
Over many years, these deposits of organic material became coal and oil. Today, these
“fossil fuels” are being depleted as they are being burned for energy. The carbon dioxide
that was once in those living organisms is then released back into the atmosphere. Clearcutting and burning forests release large amounts of carbon dioxide into the atmosphere.
Carbon dioxide is also stored and released in the oceans. Depending upon the temperature
and circulation of the water, carbon dioxide is cycled through uptake and release. Humans
play a major role in the cycling of carbon dioxide. Especially through the processes of the
burning of fossil fuels and deforestation, humans are releasing massive amounts of carbon
dioxide into the atmosphere. The amount of carbon dioxide in the atmosphere is steadily
increasing. Some of the carbon dioxide that is released into the atmosphere continues to
cycle as the oceans absorb some of the gases. Other possible ways carbon dioxide may be
removed from the atmosphere are reforestation and storage in living materials.
The Carbon Cycle
http://www.sarcs.org/new/Interest/picture%20for%20capacity/carbon_cycle_diagram.jpg
Carbon Cycle PowerPoint Presentation
Before the Activity
Students should answer the following questions before beginning the lab.
What will happen to the concentration of carbon dioxide gas in a container with a
plant in it?
What will happen to the concentration of carbon dioxide gas in the container
when there is no plant present?
Keep mint plants in the sunlight prior to the activity.
With the Students:
GLX Setup
Connect the PASPORT CO2 Sensor into Port 1 on the top of the Xplorer GLX. The Graph
Screen will automatically open with CO2 Concentration (ppm) versus Time (s).
Open the GLX setup file labeled co2 cycle.glx (check the appendix at the end of this activity).
The file is set to record data once per second.
Equipment Setup (No Plant Present)
Put the CO2 Gas Sensor into the bottle so that the rubber stopper firmly plugs the end of the
bottle.
Place the setup 30 cm from the light source. Place the heat sink between the light source and the
sampling bottle.
Record Data
Press the Start key
on the GLX.
Record data for 20 minutes.
Do not jostle the sensor or it may record erroneous data.
After 20 minutes, stop recording data.
Equipment Setup (Plant Present)
Carefully split a small plant (such as a mint plant) into four parts. Make sure that a sprig of the
plant, its associated root structure, and a portion of the soil on the roots are included in each part.
Gently push the parts of the plant into the sampling bottle. Use the blunt end of a pencil or pen to
push the plant parts into proper position in the bottle.
Put the CO2 Gas Sensor into the bottle so that the rubber stopper firmly plugs the end of the
bottle.
Make sure that the end of the sensor does not touch the plant.
Place the setup 30 cm from the light source. Place the heat sink between the light source and the
sampling bottle.
Record Data
Press the Start key
on the GLX.
Record data for 20 minutes.
Do not jostle the sensor or it may record erroneous data.
After 20 minutes, stop recording data.
Clean up as instructed.
Analysis of Data
Draw a sketch of your graph of CO2 gas concentration versus time as requested in the Lab
Report section.
Use your recorded data to find the change in carbon dioxide when there is no plant present.
In the Graph Screen, use the right-left cursor keys to move the cursor to the beginning of the data
where there is no plant present. Press F3 to open the Tools menu. Select Delta Tool and
press the Activate key. Move the cursor to the point where 20 minutes has passed. The
highlighted value on the vertical axis is the change in carbon dioxide concentration. The
highlighted value on the horizontal axis is the change in time.
Repeat the process to find the change in carbon dioxide when the plant is present.
Record your values in the Data Table in the Lab Report section.
How do your results compare with others in your class?
Do Plants Sequester Carbon Dioxide?
Name ________________________________ Date ___________
Pre-Lab Questions
Measure the carbon dioxide level in a container with a small plant (a ‘mini-terrarium’).
1.
What will happen to the concentration of carbon dioxide gas in a container without a plant
present?
2.
What will happen to the concentration of carbon dioxide gas in the container when the
plant is present?
Data
Make a sketch of CO2 concentration versus time, including labels for the y- and x-axes. Include
a graph for the trial with a plant present and without a plant.
Data
Write a description of the pattern of the graph:

No Plant Present:

Plant Present:
Data Table
Plant Present/Absent
Change in CO2 Level (ppm/20 minutes)
No Plant
Plant Present
Questions
1.
What happens to the level of carbon dioxide gas when the plant is present? Why does this
happen?
2.
What happens to the level of carbon dioxide gas when there is no plant? Why does this
happen?
3.
How would surrounding a manufacturing plant with photosynthetic organisms affect its
carbon emissions?
Do Plants Sequester Carbon Dioxide lab data sheet.doc
Attachments
Carbon Cycle Role Play
Carbon Cycle Role Play Name Tags
Safety Issues

Follow all directions for using the equipment.

Wear protective gear (e.g., safety goggles, gloves, apron).
Troubleshooting Tips:
If the desired results are not achieved make sure the mint plant is fresh, increase the amount of
mint plant in the bottle, and make sure the stopper is sealed completely.
Investigating Question: N/A
Assessment
Pre-Activity Assessment: Pre-Lab Questions
Activity Embedded Assessment: Analysis of Data
Post-Activity Assessment: Post-Lab Questions
Activity Extensions:
View the Carbon Capture video to show how engineers are developing synthetic “trees” to
remove carbon dioxide from the atmosphere.
http://www.teachersdomain.org/resource/nsn08.sci.ess.watcyc.capcarbon/
Activity Scaling/Differentiation: N/A
Additional Multimedia Support: N/A
References
Griffith, Dave. Biology with the Xplorer GLX Lab Manual. Roseville, CA: PASCO Scientific,
2005.