The Effect of Temperature on Rate of
Cellular Respiration in Pea Plants
(Pisum sativum)
G. Carroll, I. DiBianca, and A. Trumpore
Problem Statement: The effect of the temperature
of peas and their immediate surroundings is
investigated to determine a relationship between
temperature and respiration rate of germinated
peas.
Background Information and Hypothesis
- Pea plants naturally grow in cool temperate spring climates whose
temperatures range from 10°C to 20°C
- Ideal temperature range for pea plant growth is 13°C to 18°C
- Pea plants can tolerate temperatures as low as -10°C, or -30°C if snowcovered
- Pea plants do not grow well in warmer temperate or tropical climates
It is proposed that the respiration rate of peas will be greatest
at the room temperature test point (18°C), with rate
decreasing gradually to its second-highest tested rate at 5°C,
and dropping off above 18°C to it at slowest tested rate at
35°C.
Procedure - Baseline is conducted at room temperature measured at 18°C
according to baseline procedure
Colder
Warmer
1. Test tubes are prepared with basic
gas pressure probe setup
1. Test tubes are prepared with basic
gas pressure probe setup
2. Large beaker of water is cooled using
ice cubes to target temperatures (5°C
or 12°C)
2. Large beaker of water is heated on
hot plate to 35°C
3. Ice cubes are removed and beaker is
placed in styrofoam box with lid
4. Test tubes are inserted through
cardboard holder and placed in the
large beaker, as submerged as
possible
5. Data is collected for 15 minutes
6. Temperature after trial is verified
6. Setup is disassembled and cleaned
3. Test tubes are inserted through
cardboard holder and placed in the
large beaker, as submerged as
possible
4. Data is collected for 15 minutes
5. Temperature after trial is verified
6. Setup is disassembled and cleaned
Slope
(kPa/min)
Y-Intercept
(kPa)
Adjusted Slope
(kPa/min)
Results
Slope steepest at 18°C
Room Temperature (18°C)
Germinated
-0.07446
102.5
-0.06729
Non-Germinated
0.0002654
102.2
0.007433
Glass Beads
-0.007168
102.4 N/A
Steeper than that at 35°C
by 0.00014 kPa/min
Slope
(kPa/min)
Y-Intercept Adjusted Slope
(kPa)
(kPa/min)
35°C
5°C
Germinated 1
-0.03559
102.2
-0.0163 Germinated 1
-0.07704
103.2
-0.07181
Germinated 2
-0.05325
102.3
-0.03396 Germinated 2
-0.06772
103.6
-0.06249
-0.02513 Germinated Average
Germinated Average
Glass Beads
-0.01929
102.6 N/A
Glass Beads
-0.06715
-0.005227
102.3 N/A
Results
Room Temperature (18°C)
5°C
35°C
Green - Glass Beads
Blue - Ungerminated Peas
Red - Germinated Peas
Green - Glass Beads
Blue - Germinated Peas 1
Red - Germinated Peas 2
Blue - Glass Beads
Red - Germinated Peas 1
Green - Germinated Peas 2
Discussion and Conclusion
The hypothesis was disproved -The greatest measured rate of respiration was at 18°C, but only by
0.00014 kPa/min
Respiration at 5°C occurred approximately 0.34 times as fast as it did
at
18°C and 35 °C
Gradualness/suddenness of change in respiration rate as a result of change in
temperature was not determined
Decreased rate of respiration at 5°C likely resulted simply from lower
temperature, less energy, slower reaction
35°C Temperature did not denature respiration enzymes in germinated peas
Discussion and Conclusion
Questions for further study:
Why do pea plants favor cooler climates even though germinated peas
appear to respire faster when warmer?
Effects of pea plant age throughout development?
Sunlight?
Soil?
Other parts of the plant - roots, leaves?
Other factors?
Why can snow-covered pea plants tolerate colder temperatures than
non-snow-covered peas?
References
"Plants Profile for Pisum Sativum (garden Pea)." Plants Profile for
Pisum
Sativum (garden Pea). United States Department of
Agriculture, n.d. Web. 17 Jan. 2014.