report!
MATERIALS computer Vernier computer interface Logger Pro computer program Vernier CO2 Gas Sensor 25 germinating peas 25 non-germinating peas 250 mL respiration chamber ice cubes 1 L beaker two 100 mL beakers PROCEDURE 1. Plug the CO2 Gas Sensor into Channel 1 of the Vernier computer interface. Make sure the interface is connected to the computer and plugged into an outlet. 2. Prepare the computer for data collection by clicking on the Logger Pro icon on the computer desktop. Open the “11B Cell Resp” file inthe Biology with Vernier folder. 3. After about 2 minutes calibrate the sensor by pressing the tip of a pencil or end a paper clip into the hole by the letters “Cal”. If the sensor is functioning correctly, the level of CO2 should stabilize at approximately 380ppm, the amount of CO, in the atmosphere. If your sensor does not read somewhere between 300-400 ppm after calibrating let your instructor know so you can be provided with a different sensor. Once you have a sensor that functions well allow it to warm up another 3-5 minutes. Obtain 25 germinating peas and gently blot them dry between two pieces of paper towel. Use the thermometer to measure the room temperatu place in the title of Table I 4. re. Record the temperature in the appropriate 5. Place the 25 germinating peas into the respiration chamber. 6. Place the shaft of the CO2 Gas Sensor into the opening of the respiration chamber. Wait another 2 minutes 7. Begin measuring carbon dioxide concentration by clicking the green Collect) button. Data will be collected for 5 minutes and stop collecting automatically. Move your data to a stored run. To do this, choose Store Latest Run from the Experiment menu. Remove the CO2 Gas Sensor from the respiration chamber. Use a notebook or notepad to fan air across the openings in the probe shaft of the CO2 Gas Sensor for 1 minute. 8. Repeat steps 6 through 8 two more times. You will have 3 lines on your graph: Run 1, Run 2 and Run3 Now place the germinating peas in a 100 mL beaker filled with ice and a little cold water. Put the beaker with the peas and ice aside. This will prepare the peas for part II of the experiment. 9. respiration chamber with a paper towel. This is important! The sensor will not read properly if water is present in the chamber. o. Fill the respiration chamber with water and then empty it. Thoroughly dry the inside of the





