Plant Physiology – Plant Water Relations

Translocation of Water

1. The water readily available to plants for absorption by roots is

a) Gravitational water

b) Capillary water

c) Rain water

d) Hygroscopic water

2. The water potential of pure water at atmospheric pressure is

a) -2.3 bar

b) +2.3 bar

c) Zero bar

d) One bar

3. Loss of water from the stomata of leaves are known as

a) Guttation

b) Exudation

c) Transpiration

d) Evaporation

4. During rainy season wooden doors are difficult to open or closure because of

a) Plasmolysis

b) Imbibition

c) Osmosis

d) Diffusion

5. Plasmolysis occurs due to

a) Absorption

b) Osmosis

c) Endoosmosis

d) Exosmosis

6. The marine animals that kept in fresh water burst. It shows the process of

a) Exosmosis

b) Endoosmosis

c) Plasmolysis

d) Deplasmolysis

7. Cooling of plants is caused by

a) Guttaion

b) Photorespiration

c) Transpiration

d) Assimilation

8. Active uptake of minerals by roots mainly depends on the

a) Availability of oxygen

b) Temperature

c) Light

d) Availability of CO2

9. The hormone which signals the closure of stomata is

a) Auxins

b) Cytokinine

c) Gibberelline

d) Abscisic acid

10. Water absorption takes place through

a) Lateral roots

b) Root cap

c) Root hairs

d) Tap root

11. Which of the following is an anti-transpirant

a) PMA

b) PAN

c) IAA

d) AUG

12. What is the action spectrum of transpiration?

a) Orange and red

b) Green and ultraviolet

c) Blue and red

d) None of these

13. Which one of the following is used for measuring the rate of transpiration?

a) Porometer

b) Osmometer

c) Moll’s experiment

d) Potometer

14. Transpiration is least in

a) High atmospheric humidity

b) good soil moisture

c) high wind velocity

d) dry environment

15. Stomata open at night and close during day time in

a) Xerophytes

b) Mesophytes

c) Succulents

d) Hydrophytes

Answers
1- b6-b11-a
2- c7-c12-c
3-c8-a13-d
4-b9-d14-a
5-d10-c15-c