Question

What is Ganong’s potometer used for? Write any two limitations of this apparatus.

Answer 1

Ganong’s potometer is used to measure the rate of transpiration.

Limitations:

i) Introducing air bubble is difficult.

ii) Amount of water loss through transpiration cannot be measured.

Answer 2

Answer:

Potometer is an instrument for measuring the rate of transpiration by shoots through measuring the rate of their water absorption, as the two are nearly equal. This method is used to measure transpiration in leafy twigs e.g., Ganong's protometer.

t doesn't measure the extent and duration of transpiration either.

It only measures the amount of uptake of water by the plants. The water taken up can be used for Transpiration or photosynthesis too. Hence the measurement is not very accurate.