Plant Respiration and Photosynthesis
012-10974 r1.04
Plant Respiration and Photosynthesis
Introduction
Journals and Snapshots
The Snapshot button is used to capture the
screen.
The Journal is where snapshots are stored
and viewed.
The Share button is used to export
or print your journal to turn in your
work.
Each page of this lab that
contains the symbol
should be inserted into your
journal. After completing a
lab page with the snapshot
symbol, tap
(in the
upper right hand corner) to
insert the page into your
journal.
Note: You may want to take a
snapshot of the first page of
this lab as a cover page for
your journal.
Plant Respiration and Photosynthesis
Lab Challenge
• Do plants perform cellular respiration
in addition to photosynthesis?
Plant Respiration and Photosynthesis
Background
Photosynthesis
• The process of photosynthesis occurs in the chloroplasts of plants.
• Light is necessary for the entire photosynthesis process to occur.
• The formula for photosynthesis is:
6CO2 + 6H2O + LIGHT ENERGY ----> C6H12O6 + 6O2
• Carbon dioxide, water, and light are required to produce glucose and oxygen.
Plant Respiration and Photosynthesis
Self Check
1. If you were measuring carbon dioxide levels in a
terrarium during photosynthesis, you would expect
to see the levels ________.
a) increase
b) decrease
c) stay the same
This image is a reminder to
tap
to take a snapshot
of the page after you have
entered your response.
Plant Respiration and Photosynthesis
...Background
Cellular Respiration
• The process of cellular respiration occurs in the mitochondria of ALL cells.
• Cellular respiration converts the glucose made by photosynthesis into ATP
(adenosine triphosphate), which is the energy source that is usable by cells.
• The formula for cellular respiration is:
C6H12O6 + 6O2 ----> 6CO2 + 6H2O + Energy (ATP molecules)
• Glucose and oxygen produce carbon dioxide, water and ATP.
Plant Respiration and Photosynthesis
Self Check
2. If carbon dioxide levels were being monitored
inside a terrarium, you would expect to see an
increase in CO2 levels when the plants were in
___________.
a) darkness
b) light
c) Canada
Plant Respiration and Photosynthesis
Safety
• Follow all common lab safety procedures.
• Do not allow the CO2 sensor to get wet!
Plant Respiration and Photosynthesis
Materials and Equipment
Collect all of these materials before beginning the lab.
• PASPORT CO2 Gas Sensor
• Sensor extension cable
• Sampling bottle (included with the
sensor)
• Large beaker or aquarium (to act as
a heat sink)
• Box or heavy cloth
• Aluminum foil
• Lamp, 100-watt
• Mint plant
• Water, 1 L
Plant Respiration and Photosynthesis
Sequencing Challenge
A. Cover the bottle
with a box or cloth
and record CO2
production in the
dark.
B. Record CO2
production when
the plant is exposed
to the light.
C. Analyze the
changes in CO2
production in dark
vs. light.
D. Add several stems
and leaves of a small
plant into the
sampling bottle.
The steps to the left are part
of the procedure for this lab
activity. They are not in the
right order. Determine the
correct sequence of the
steps, then take a snapshot
of this page.
Plant Respiration and Photosynthesis
Setup: Darkness
1. Attach the Carbon Dioxide Gas Sensor to a
sensor extension cable and connect it to the
SPARK Science Learning System.
2. Add 25 mL of water to the sample bottle.
3. Gently push several stems of the plant into the
sampling bottle. Try to arrange the leaves so
that they are facing outward.
4. Calibrate the sensor by pushing and releasing
the green button on the sensor. When the
green light in the button begins flashing again,
the sensor is calibrated.
Plant Respiration and Photosynthesis
Prediction: General
Q1: Why do you think that water is needed in the sample bottle?
Plant Respiration and Photosynthesis
Collect Data: Darkness
1. Place the CO2 Gas Sensor firmly into the sampling
bottle.
2. Carefully cover the sample bottle with a box or
heavy cloth to block out any light.
3. Tap
to begin data collection.
4. Record data for 10 minutes and then tap
data collection.
to stop
Q2: What do you think will
happen to the CO2 level
in the bottle while the
plant is in the dark?
Explain why.
Plant Respiration and Photosynthesis
Plant Respiration and Photosynthesis
Setup: Light
1. Remove the cloth or box from the sampling bottle
and place the bottle on aluminum foil.
2. Place a large beaker of water or aquarium
between the light source and the beaker.
3. Turn on the light source and wait 3 minutes to
allow photosynthesis to begin.
Q2: What is the purpose of
the aluminum foil?
Q3: What is the purpose of
the beaker/ aquarium
full of water?
Plant Respiration and Photosynthesis
Collect Data: Light
1. Tap
to begin data collection.
2. Record data for 10 minutes and then tap
stop data collection.
to
Q4: What do you think will
happen to the CO2 level
in the bottle while the
plant is in the light?
Explain why.
Plant Respiration and Photosynthesis
Data Analysis
1. Determine the change in
CO2 concentration for both
runs, and record the
information in the data
table on the next page.
* To Find the Difference
Between Two Data Points:
1. Tap
to open the tools
palette.
2. Tap
and then tap two
points on the data run.
3. Adjust using both
buttons
and then tap
4. Tap
to display the
differences.
Plant Respiration and Photosynthesis
Data Analysis
2. Record the initial, final,
and change in CO2
concentration for all runs,
in the data table to the
left.
*To Enter Data into a Table:
1. Tap
to open the tool
palette.
2. Tap
then tap a cell in the
data table to highlight it in
yellow.
3. Tap
to open the
Keyboard screen.
Plant Respiration and Photosynthesis
Analysis
1. What happens to the level of carbon dioxide gas when the plant is in the
darkness? Why does this happen?
Plant Respiration and Photosynthesis
Analysis
2. What happens to the level of carbon dioxide gas when the plant is in bright
light? Why does this happen?
Plant Respiration and Photosynthesis
Analysis
3. Was there greater change in the level of carbon dioxide in the darkness
or light? Explain.
Plant Respiration and Photosynthesis
Synthesis
1. What part of the activity shows the effect of cellular respiration on carbon
dioxide levels in the chamber?
Plant Respiration and Photosynthesis
Synthesis
2. What is meant by the term "Carbon Cycle" in this activity?
Plant Respiration and Photosynthesis
Synthesis
3. Explain how photosynthesis and cellular respiration are dependent on one
another.
Plant Respiration and Photosynthesis
Synthesis
4. If plants are able to photosynthesize, why do they also have to go through
cellular respiration?
Plant Respiration and Photosynthesis
Synthesis
5. Write a conclusion for this experiment based on the following question,
"Does the level of carbon dioxide gas produced in a closed environment
change in dark and in bright light conditions?"
Plant Respiration and Photosynthesis
Multiple Choice
1. Which of the following are required for
photosynthesis to occur?
a) light
b) chloroplasts
c) carbon dioxide
d) all of the above
Plant Respiration and Photosynthesis
Multiple Choice
2. Respiration can occur in a plant ____________.
a) in the light
b) in the dark
c) when oxygen is present
d) all of the above
Plant Respiration and Photosynthesis
Multiple Choice
3. When a bright light is turned on a plant, which
reaction(s) take place?
a) photosynthesis only
b) cellular respiration only
c) photosynthesis and cellular respiration
d) nothing
Plant Respiration and Photosynthesis
Multiple Choice
4. What is shown in the graph of CO2
concentration vs. Time for a plant?
a) respiration then
photosynthesis
b) photosynthesis then
respiration
c) light-dependent
reactions only
d) light-independent
reactions only
Plant Respiration and Photosynthesis
Congratulations!
You have completed the lab.
Please remember to follow your teacher's instructions for cleaning-up and submitting
your lab.
Plant Respiration and Photosynthesis
References
Images are taken from PASCO documentation, public domain clip art, or Wikimedia Foundation Commons
http://commons.wikimedia.org/wiki/File:Narzisse.jpg
http://commons.wikimedia.org/wiki/File:Peppermint_and_Corsican_mint_plant.jpg
http://commons.wikimedia.org/wiki/File:Rose_Geranium.jpg
http://commons.wikimedia.org/wiki/File:Sunflowers.jpg