The figure shows one type of potometer used by a student to investigate transpiration.

a. i. Suggest a hypothesis the student could test about the transpiration of a mesophyte (a plant adapted to a moist environment) and a xerophyte (a plant adapted to a dry environment).

ii. Outline a procedure involving the potometer that the student could use to test this hypothesis.

iii. The capillary tube measures the distance moved by the water. Explain how the actual volume of water lost can be calculated.

b. Sketch a graph to predict the expected results of the investigation.

c. i. The student then measured the surface area of the leaves by tracing the outline on a grid and counting the number of squares covered by the leaves. This area was doubled. 

Mesophyte:

surface area of leaves = 36 cm²

water loss in 30 minutes = 0.018 cm³

Calculate the rate of water loss in cm³ m⁻² min⁻¹. Show all the steps in your calculation.

ii. State a statistical test that the student could use to find out if the difference in water loss between the two types of leaf is significant. State a reason for your choice.

Transcribed Image Text:

syringe used to push water into capillary tube graduated capillary tube to measure leafy shoot water movement rubber bung beaker of water