SMT. SULOCHANADEVI SINGHANIA SCHOOL, THANE
STD 12 Biology
Absorption of water by roots and Transpiration Worksheet
1
Mention the most significant function or role of the Guard cells.
2
Define the following:
a) Root pressure
b) Water potential
c) Diffusion
d) Osmosis
e) Plasmolysis
f)
Turgor pressure
3
State the significance of osmosis
4
Explain stomatal movement based on K+ ion transport mechanism
5
Name the scientist associated with cohesion tension theory
6
Give four compatible difference between transpiration and guttation
7
Describe the path of ascent of sap due to transpirational pull
8
Give an account of different types of soil water
9
Elaborate ABA, OP, DPD
10 Define TP. Explain significance of turgidity in plants
11 Differentiate between:
a) Active and passive absorption of water
b) Diffusion and osmosis
12 Which part of the soil water is available to plants for absorption by roots?
13 Explain briefly the movement of water from the soil across root to the xylem vessel
14 Give reasons- the water potential of pure water changes when solute is added to it
15 Mention one difference between the following:
a. Turgor pressure and wall pressure
b. Plasmolysis and crenation
c. Osmosis and diffusion
d. Hygroscopic water and capillary water
e. Chresard and Echard
f.
DPD and water potential
g. Exosmosis and endosmosis
h. Turgid and flaccid
i.
Osmotic potential and osmotic pressure
16 Write brief explanatory notes on:
j. Root pressure
k. Water potential
l.
Significance of osmosis and diffusion
m. Diffusion pressure deficit
n. Importance of water in plants
o. Advantages of turgidity to plants.
17 Answer the following:
p. What happens to the water potential of pure water when solutes are added to it?
q. What are anti-transpirants? Give an example.
r.
Name the specialized structures through which guttation occur.
18 “Transpiration is a necessary evil”. Justify.
19 Explain the theories for the absorption of water by the roots.
20 Discuss briefly the various theories put forth to explain the ‘ascent of sap’.
21 Give an account of cohesion tension transpiration pull theory.
22 Differentiate between transpiration and evaporation
23 What are the external factors affecting the rate of absorption by the roots.
24 Osmosis is a special kind of diffusion. Explain.
25 Give reasons for the following:
a) Silicon emulsions are applied on the surface of the leaves.
b) Water potential of a solution is represented by a negative sign.
c) Plant cells do not burst when placed in water.
d) Dry raisins swell when placed in water
e) When your foot is sprained and swollen the doctor advises you to keep your foot in hot
water containing plenty of common salt.
f)
salt is added in excess to pickles
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