2O
Cellular Respiration Lab Report
Introduction
Cellular respiration is the breaking down of food molecules and converting them into energy. Glucose is oxidized as long as there is the presence of oxygen and if not, fermentation will begin to take place. All organisms, including plants and animals, go through cellular respiration. This process creates energy for the body to exert in the form of ATP. This lab is to test if peas go through cellular respiration before germination.
Hypotheses
Part I: If the peas are germinated and placed in the jar with the CO2 gas sensor, then they will undergo cellular respiration (same for lima beans).
Part II: If the peas are non-germinated and placed in the jar with the CO2 gas sensor, then they will not undergo cellular respiration.
Materials
LabQuest
25 germinated peas
LabQuest App
25 non-germinated peas
Vernier CO2 Gas Sensor ice cubes two 100 mL beakers thermometer 250 mL respiration chamber
Logger Pro (optional)
Procedure
Part I
1. If your sensor has a switch, set it to the Low (0–10,000 ppm) setting. Connect the CO2 Gas Sensor to LabQuest and choose New from the File menu. If you have an older sensor that does not auto-ID, manually set up the sensor.
2. Measure the room temperature using a thermometer and record the temperature in Table 1.
3. Obtain 25 germinated peas and blot them dry between two pieces of paper towel.
4. Place the germinated peas into the respiration chamber.
5. Place the shaft of the CO2 Gas Sensor in the opening of the respiration chamber.
6. Wait one minute, then start data collection. Data will be collected for 10 minutes.
7. When data collection has finished, a graph of carbon dioxide gas vs. time will be displayed.
8. Remove the CO2 Gas Sensor from the respiration chamber. Place the peas in a 100 mL beaker filled with cold water and an ice cube. The cold water will prepare the peas for part II of the experiment.
9. Use a notebook or notepad to fan air across the openings in the probe shaft of the CO2 Gas Sensor for 1 minute. 10. Fill the respiration chamber with water and then empty it. Thoroughly dry the inside of the respiration chamber with a paper towel. 11. Perform a linear regression to calculate the rate of respiration.
a. Choose Curve Fit from the Analyze menu.
b. Select Linear for the Fit Equation. The linear-regression statistics for these two data columns are displayed for the equation in the form y = mx + b where x is time, y is CO2 concentration, m is the slope, and b is the y-intercept.
c. Enter the slope, m, as the rate of respiration in Table 2.
d. Select OK.

12. Store the data from the first run by tapping the File Cabinet icon. 13. Repeat Steps 3–12 substituting the germinated peas with non-germinated peas. In Step 8 place the non-germinated peas on a paper towel and not in the ice bath.
Part II 14. Remove the peas from the cold water and blot them dry between two paper towels. 15. Repeat Steps 3–11 using the cold peas. When you have completed Step 11 skip directly to Step 16. 16. Graph all three runs of data on a single graph.
a. To view a graph of pH vs. volume showing all three data runs, tap Run 3 and select All Runs.
b. All three runs will now be displayed on the same graph axes.
c. Use the displayed graph and Tables 1 and 2 to answer the questions below.
Data
Lima Beans
Condition
Temperature (Celsius)
Room
23
Cold Water
8

Lima Beans
Rate of respiration (ppm/s)
Germinated, room temperature
94.461
Non-germinated, room temperature
0.76294
Germinated, cool temperature
84.543

Peas
Condition
Temperature (Celsius)
Room temperature
23
Cold Water
12

Peas
Rate of respiration (ppm/s)
Germinated, room temperature
0.94135
Non-germinated, room temperature
-0.048
Germinated, cold water
0.82498
Data Analysis
We have the evidence to support the fact that respiration did indeed occur in both the peas and the lima beans. In our tables, we used the CO2 gas sensors to find the rate of respiration found in the peas and lima beans