M.Sc. (Semester IV) (CBCS) Examination Mar/Apr-2018
Botany
ENVIRONMENTAL PLANT PHYSIOLOGY
Time: 2½ Hours
Max. Marks: 70
Instructions: Answers any five questions. Figures to the right indicate full marks. Question 1 is compulsory. Answer any two questions from Q.2, 3 4. Answer any two questions from Q.5, 6 7.
Q.1
Rewrite the following sentences by choosing correct alternative:-
14
Tissue water potential is measured in the units of
amperes
volts
calories
megapascals
Desert ephemerals are an example of type of plants.
drought resistant
drought escape
drought tolerant
drought sensitive
Photorespiration in C3 plants gets when CO2 level is increased.
Increased
Reduced

Maintained
Balanced
Depletion of ozone increases the amount of radiations reaching the globe.
Visible
UV
IR
Gamma
Cell membranes of plants resistant to chilling injury contain fatty acids in their lipid bilayer.
saturated
long chain
unsaturated
short chain
SOD catalyzes the reduction of into hydrogen peroxide.
molecular oxygen
singlet oxygen
ozone
superoxide
Acid rain is caused by higher concentrations of in the atmosphere.
NOx and SO2
NO2 and O3
SO2 and O3
CO2 and SO2
is a halophyte.
Suaeda
Sugarbeet
Date palm
Cotton
Accumulation of phytohormone occurs during waterlogging.
IAA
Cytokinin
O
Ethylene
ABA
10) In sodic soils a high concentration of is present.
salt
sodium
potassium
sand
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SLR-UD-134
11) Potassium ions play an important role in
stomatal movements
protein synthesis
cell signaling
none of the above
12) Manganese toxicity in plants is identified by
Chlorosis
Necrosis
Brown spots surrounded by chlorotic zones
All the above
13) Disease occurs in the plants when the pathogen lacks
R genes
avr genes
DIR1 genes
None of these
14) are considered to be the indicators of heavy metal stress.
Compatible solutes
Phytochelatins
LEA proteins
HSPs
Q.2
What is disease? Describe biochemical changes occurring in the host tissue during fungal infection.
14
Q.3
Give an account of effect of salt stress on plant metabolism.
Write a note on mechanism of slat tolerance in higher plants.
14
Q.4
Describe in brief:-
Effects of water stress on plant metabolism.
Structural adaptations in xerophytes in response to water stress.
14
Q.5
Write on
14
Effect of SO2 on plant metabolism
Chilling injury
Q.6
Give an account of
14
Reactive oxygen species in plants and their origin
Antioxidants in plants and their role
Q.7
Write a short note (Any three)
14
Proline accumulation in plants
Heat shock proteins
Effects of flood and tolerance mechanism in plants
Impact of elevated CO2 concentration on plants