Question

Ganong’s potometer is used to measure
A.Photosynthesis
B.Respiration
C.Transpiration
D.Guttation.

Answer 1

Hint: Potometer is a device which is used for measurement the rate of transpiration in the shoots of the plants, by measuring rate of absorption water from the soil as it is equal to the rate of transpiration.

Complete answer:
1.Photosynthesis: It is the process by which green plants obtain their food by transforming light energy into chemical energy. Photosynthesis starts by absorption of light energy by a pigment called the chlorophyll. It is a very common process in plants.

2.Respiration: It is the process in which an organism obtains energy (in the form of ATP) from its food. In this process energy is produced by breakdown of simpler food molecules such as glucose. This energy is utilized by various metabolic reactions occurring in our body.

3.Transpiration: It is a process occurring in plants in which water is lost by plants from aerial parts such as leaves, flowers etc. by its evaporation. Leaves undergo transpiration through stomata.

4.Guttation: It is a phenomenon of loss of water in the form of water droplets from small pores in leaves called hydathodes.
Ganong’s potometer: It is a device which is used to measure water loss through a stem during the transpiration process. It is generally used in labs to measure transpiration in a shoot twig.

Hence, the correct answer is option (C)

Note: Guttation is mainly observed during morning or evening time, when rate of absorption by roots is more than rate of transpiration. So, plants lose their excess of water by guttation.