Question

Potometer works on the priniciple of:

• A. Potential difference between the tip of the tube and that of the plant
• B. Amount of water absorbed equals the amount transpired
• C. Osmotic pressure
• D. Root pressure

Answer 1

The correct option is B Amount of water absorbed equals the amount transpired

Potometer is an instrument used to measure the rate of transpiration.

An air bubble is inserted in the instrument as is shown in the figure. Water absorbed by the roots from the apparatus is lost through the leaves by transpiration. This causes the air bubble to move along the graduations of the tube. Readings are taken for the movement of the bubble and thus the amount of water that is lost in transpiration is calculated.