Transpiration

• What is the first step in the procedure for investigating transpiration?

  Cut a shoot underwater
• Why is it important to cut the shoot underwater?

  To prevent air entering the xylem
• What should be used to seal gaps in the apparatus?

  Vaseline
• Why should the leaves of the shoot be dried?

  Wet leaves will affect the results
• What should be done after removing the capillary tube from the beaker?

  Allow a single air bubble to form
• What is the purpose of setting up the environmental factor?

  To investigate its effect on transpiration
• How long should the plant adapt to the new environment?

  5 minutes
• What should be recorded after allowing the plant to adapt?

  The starting location of the air bubble
• What should be done after recording the starting location?

  Leave for a set period of time
• What is recorded after the set period of time?

  The end location of the air bubble
• What should be changed to investigate different factors?

  Light intensity, wind speed, humidity, or temperature
• How many environmental factors should be changed at once?

  Only one
• What is the purpose of resetting the bubble?

  To allow for a new measurement
• What does the distance the bubble travels indicate?

  The rate of transpiration occurring
• What happens if the bubble travels further in the same time period?

  Transpiration is occurring faster
• What happens if the bubble travels a shorter distance?

  Transpiration is occurring slower
• How can Environmental factors be investigated?

  • Airflow: Set up a fan or hairdryer
  • Humidity: Spray water in a plastic bag and wrap around the plant
  • Light intensity: Change the distance of a light source from the plant
  • Temperature: Temperature of room (cold room or warm room)