pratical 10

• Set up a potometer.
• Cut the leafy shoot underwater to prevent air bubbles from entering the vascular tissues and insert into the potometer.
• Use vaseline to seal gaps in the potometer to make sure it is airtight.
• Set up the necessary environmental factors.
• Temperature: use a temperature-controlled room or immerse potometer in a thermostatically controlled water bath.
• Humidity: Wrap the shoot in a plastic bag with varying degrees of vapour.
• Wind speed: Set up a fan with different speeds.
• Light intensity: Set up a lamp at different distances from the shoot.
• Allow time for the apparatus to equilibrate.
• Record the starting position of the air bubble in the capillary tube.
• Leave the apparatus for 1 hour.
• Record the final position of the air bubble and calculate the distance moved, calculate the volume of water absorbed by the plant in the period of time.
• Repeat steps 1-8, changing the factor at fixed intervals.
• Plot a graph of the ‘factor’ (x- axis) against the volume of water taken up by the plant in 1hour (y-axis).