Question

Complete the following statement by choosing the correct option out of those given within brackets.
Potometer is an instrument used for measuring the rate of (transpiration/evaporation).

Answer 1

1. The rate of transpiration is measured by Ganong's potometer.
2. The device consists of a vessel containing water.
3. A cut stem of a plant or a small plant with roots is placed in this vessel.
4. It is sealed with wax or any other material. This vessel is connected to a water reservoir and a graduated capillary tube.
5. Apparatus is kept for some time at an optimum climatic condition.
6. The movement of bubbles through the graduated capillary tube is considered a measure of the rate of transpiration.
7. 

Transpiration	Evaporation
It is a biological process.	1. It is a physical process.
2. Transpiration is a slow process.	2. Comparatively a fast process.
3. Occurs in living tissues.	3. Involves non-living matter.
4. In the process of transpiration water is lost from plant cells	4. In this process, water is lost from the surface of plant parts
5. Occurs through stomata, cuticle, or lenticel.	5. It occurs from the entire outer surface
6. Occurs during the daytime.	6. Occurs during the day as well as at night

Final answer: Potometer is an instrument used for measuring the rate of transpiration.