One branch of the plant, the humidity sensor and the temperature sensor are placed into the polythene bag and the end tied up with string. The graph is set to show humidity. The spreadsheet is set to show both humidity and temperature. Once the experiment is setup, leave the humidity sensor to log data for approximately 20 minutes. The temperature sensor is there to prove the temperature is kept constant.
Plants pump up water from the soil.
Name some environmental stimuli that would effect the rate of transpiration. Explain whether they would increase or decrease the rate of transpiration. Further study Further study could involve comparing the transpiration of a control leaf to one smeared in Petroleum jelly.