Name ____________________________ Period ___
How does temperature affect cricket
respiration?
PA Standards
2.3.11A .Select and use appropriate units and tools to measure to the degree of accuracy required in particular
measurement situations.
3.2.10/12 B: Evaluate experimental information for appropriateness and adherence to scientific processes
3.3.10/12 B: Analyze the chemical and structural basis of living organisms
3.7.10 B; 3.7.12 B: Apply/evaluate appropriate instruments and apparatus to examine/accurately measure materials
and processes
Introduction and background
In cold-blooded organisms, poikilotherms, there is a link between the temperature of the environment and
the organism’s metabolic rate. Reptiles are a common example of a cold-blooded organism with which
most people are familiar. If you have ever seen a lizard or snake in the early morning when the air and
ground are cool, you may have noticed how slowly they move. They move slowly when the environment
is cold because they require heat from their surroundings to increase their internal temperature and
metabolism. Once their internal body temperature has warmed, they can metabolize foods more quickly
and produce the energy they need. Cellular respiration is the process of metabolism where sugars are
broken down. Under aerobic conditions, respiration yields chemical energy, carbon dioxide, and water.
C6H12O6
glucose
+ 6 O2 →
oxygen
6 CO2 + 6 H2O +
ATP
carbon
water
energy
dioxide
Crickets will be used to study the effect of temperature on the metabolism of cold-blooded organisms.
You will determine how temperature affects the respiration rate of crickets by monitoring carbon dioxide
production with a CO2 Gas Sensor.
Guiding Questions
We will test cold temperatures (5-10° C), room temperature (~ 20° C), and warm temperatures (35-40°
C). Which temperature do you predict will give the highest rate of respiration? _______
Which temperature will give the lowest rate of respiration? _________________
Vocabulary
Cellular respiration: The oxygen-requiring stage in the breakdown and release of energy from fuel
molecules such as glucose to form ATP.
Poikilotherms: Organisms whose internal temperatures vary, often matching the temperature of their
immediate environment.
Materials
Computer with interface
Vernier CO2 Gas Sensor
Stainless steel temperature probe
5 adult crickets
Balance
250 ml respiration chamber
Plastic beaker (to mass crickets)
1L glass beaker (for water bath)
Stop watch
Funnel (for transfer of crickets)
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Susquehanna University
Safety
Do not place the crickets at temperatures below 5° C or above 40° C. Extreme temperatures may kill the
crickets.
Procedure
1. Check that Effect of Temperature on Cold-Blooded Organisms is on your computer screen and that
the CO2 Gas Sensor reading in lower left corner is below 1000 ppm. If not, show your teacher.
2. Determine mass of your crickets: Zero your balance, record the mass of your plastic beaker, then
add five adult crickets and record the mass again on your Data sheet on page 3.
CO2 Gas Sensor
3. Place the crickets into the respiration chamber using the funnel and then place the CO2 Gas Sensor in
the respiration chamber pushing with a gentle pressure. Do not twist the shaft of the sensor or you
may damage it. You will do your first data collection at room temperature. Be sure to record the
actual room temperature on your data sheet Table 1.
4. Wait one minute and then begin measuring carbon dioxide concentration by clicking Collect . Data
will be collected for 5 minutes. You do not have to stop the collection–the icon will turn green again
when time is up.
5. Determine slope of the line seen on the computer screen by:
a. Click the Regression button, , to perform a linear regression. A floating box will appear with
the formula for a best fit line.
b. Record the slope of the line, m, in the slope column of Table 1.
c. Save your data by clicking “Ctrl L”.
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6. Before testing other temperatures you must remove built up CO2 from the respiration chamber :
 Remove the CO2 Gas Sensor from the respiration chamber. Place the crickets in the plastic
beaker.
 Fan air across the shaft of the sensor to clear the carbon dioxide
 Fill the respiration chamber with water, empty it, and dry it with a paper towel.
 Return the same crickets to the respiration chamber.
7. While your room temperature test is collecting data, set up your water bath for your assigned
temperature: A water bath is just a large beaker no more than half full of water at a certain
temperature. Use ice or warm water to get to your assigned temperature. The water bath will allow
the crickets to remain at a constant temperature during your test. Use the stainless steel temperature
probe to check the water temperature by submerging it into the water bath and read the temperature
from the computer screen right above the computer graph. Record your actual temperature in Table 1.
8. Place the respiration chamber in the water bath you have made. It will float/balance in the beaker so
you do not need to hold it. Do not hold by the sensor and do not get the gas sensor wet!
9. Wait one minute and then begin measuring carbon dioxide concentration by clicking
will be collected for 5 minutes. You do not have to stop the collection.
Collect
. Data
10. Determine the rate of respiration as you did in Step 5.
11. At the end of your collections print your graph by selecting File: Print Graph.
Data Tables
Mass of crickets
(A) Beaker: __________g (B) Beaker + Crickets: __________g Crickets: _____g
To calculate the mass of the crickets alone:
(B) Beaker + crickets in grams – (A) Beaker in grams = Crickets in grams
Table 1
Target Temperature
Range(°C)
Actual
temperature
(°C)
Lab Group Cricket Data
Order of
tests
Slope (m)
(ppm/min)
Respiration rate
(ppm/min/g)
(1,2,3)
Room temp
5 – 10°C
35 – 40°C
To calculate respiration rate, divide the slope (m) of the data line by the mass of the crickets. Record this
value as the rate of respiration in the last column of the Lab Group Cricket Data table.
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Sharing Class Data: Respiration Rate (ppm/min/g)
5 – 10°C
15 – 20°C
35 – 40°C
Average=
Average=
Average=
Questions:
1. Look at your data. How does temperature affect the rate of respiration in crickets?
How does this compare to your prediction?
2. Why do we use the mass of the crickets in our calculation of respiration rate?
3. What factors might affect the results of this experiment?
4. Predict the rate of respiration for crickets at 60°C. Explain.
Adapted from Biology with Vernier
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Teacher Notes
Time needed to complete lab: Lab can be completed in a 40 minute period with all groups taking
baseline respiration readings at room temperature and groups assigned to a single temperature variable.
Some groups may be able to complete a third data collection period of a temperature of their choice. Data
will then need to be shared in the follow up class period.
Target grade level: This lab is adaptable to a range of levels. Middle school life science students can
complete the data collection with a basic level of overall changes in metabolism with temperature. The
lab is best suited to the high school biology 1 students. This lab may be incorporated into the AP biology
cellular respiration lab #5.
Objectives: Students will measure concentrations of carbon dioxide using a carbon dioxide gas sensor.
Students will determine the rate of respiration of crickets at varying temperatures. Students will apply
their findings to a description of factors affecting metabolic functions.
Major concepts: This lab relates to the process of cellular respiration. It provides insight on methods to
measure rates of reactions and experience in data collection, observation of test organisms, and methods
to report results.
Preparation: Access to ice and warm water is needed. Station set up is the only advance preparation.
Typical results: Lowest respiration rate occurs with the lower temperature and increases as the
temperature is increased within the range of the suggested temperatures. Occasionally the low
temperature gives a higher than expected rate of respiration but students report the crickets to be
extremely active. Suggest that students record behavioral observations of their crickets as they move
from one temperature to another to help interpret data. The room temperature run gives a baseline for
comparison between groups. Respiration rates are usually similar for that run and then changes can be
observed from that baseline. The absolute amount of time the crickets are exposed to the temperature also
affects the rate. (longer may equal slower.) If one does 3 temperatures, noting the order of the runs is
important – one cannot compare absolute respiration rates between groups when the crickets have already
been slowed or stimulated by previous temperature changes. Within one groups data you can note
relative increases and decreases. The cooled crickets may appear dead but most times revive when
gently warmed. If students observe crickets very still they should remove the crickets from the ice bath.
Answers to questions:
1. Look at your data. How does temperature affect the rate of respiration in crickets? Cold-slowest rate;
warm;highest rate.How does this compare to your prediction? Varies with group
2. Why do we use the mass of the crickets in our calculation of respiration rate? Crickets vary in size and
this will impact the amount of carbon dioxide they produce. Using the mass allows us to compare
data among groups.
3. What factors might affect the results of this experiment? Activity of the crickets; length of time at the
temperature; condition of crickets
4. Predict the rate of respiration for crickets at 60°C. Explain. The rate of respiration should be very
low. Crickets cannot survive at that high a temperature.
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Pre-Quiz
Susquehanna University
Student Name: __________________________________________
1. Poikilotherms are organisms which
a) are able to survive freezing temperatures
b) maintain body temperature at a constant level
c) warm their environment
d) match the temperature of their immediate environment
2. Cellular respiration
a) uses ATP
b) produces carbon dioxide
c) occurs only in plants
d) produces oxygen
3.
The highest rate of respiration is found at
a) 5°C
b) 60°C
c) 15°C
d) 35°C
4. Using the mass of the crickets to determine the rate of respiration
a) gives us a bigger number
b) allows us to compare data between groups
c) shows how healthy the crickets are
d) is the same as the slope of the line
5. The rate of carbon dioxide change with time is shown by the ______________________.
a) intercept
b) carbon dioxide level at 5 minutes
c) slope
d) amount of time in ice
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Post-Quiz
How Does Temperature Affect Cricket Respiration?
Susquehanna University
Student Name: __________________________________________
1. The highest rate of respiration is found at
a) 15°C
b) 60°C
c) 35°C
d) 5°C
2. Cellular respiration
a) occurs only in plants
b) uses ATP
c) produces carbon dioxide
d) produces oxygen
3. Using the mass of the crickets to determine the rate of respiration
a) gives us a bigger number
b) shows how healthy the crickets are
c) is the same as the slope of the line
d) allows us to compare data between groups
4. Poikilotherms are organisms which
a) warm their environment
b) maintain body temperature at a constant level
c) are able to survive freezing temperatures
d) match the temperature of their immediate environment
5. The rate of carbon dioxide change with time is shown by the ______________________.
a) slope
b) carbon dioxide level at 5 minutes
c) amount of time in ice
d) intercept
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