question_answer 1)
During cell enlargement phase of growth, molecules of new cell wall material are inserted between the original molecules of stretched wall. This process is known as [DPMT 1980]
A)
Intussusception done
clear
B)
Apposition done
clear
C)
Integration done
clear
D)
None of the above done
clear
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question_answer 2)
If a planter is interested in obtaining a good crop of tea leaves from a single plant, he should
A)
Feed auxin to the plant through soil done
clear
B)
Remove the apical bud of the main shoot and the branches done
clear
C)
Cut off the tip of the plant and then apply auxins to the cut end done
clear
D)
Supply auxin from the tip of the plant as well as through roots done
clear
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question_answer 3)
Phytohormones are [CBSE PMT 1990]
A)
Hormones regulating growth from seed to adulthood done
clear
B)
Growth regulators synthesised by plants and influencing physiological processes done
clear
C)
Hormones regulating flowering done
clear
D)
Hormones regulating secondary growth done
clear
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question_answer 4)
Match the table (1) Maheshwari (I) Pre-sowing treatment of seeds of Phaseolus aureus with IAA (2) Das (II) Avena curvature test (3) Went (III) Work on seedless fruit in cucumber (4) Chakravarty (IV) Successful culture of a ovule of Papaver using IAA and kinetin
A)
A - IV B - III C - II D - I done
clear
B)
A - I B - II C - III D - IV done
clear
C)
A - II B - III C - IV D - I done
clear
D)
A - III B - I C - IV D - II done
clear
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question_answer 5)
Match the following 'A' 'B' (1) Auxin (I) Ripening and maturity of fruits (2) Gibberellin (II) Differentiation of xylem elements (3) Cytokinin (III) Prevention of genetic and physiological dwarfism (4) Ethylene (IV) Found from tumour tissue of tobacco
A)
(1) - IV (2) - III (3) - II (4) - I done
clear
B)
(1) - IV (2) - II (3) - III (4) - I done
clear
C)
(1) - II (2) - III (3) - IV (4) - I done
clear
D)
(1) - III (2) - IV (3) - II (4) - I done
clear
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question_answer 6)
In tissue culture experiments in tobacco callus, it was seen that when the culture medium contains 2 ppm of IAA and 2 ppm of kinetin an undifferentiated mass of callus is produced. If the ratio of kinetin to IAA is increased
A)
The callus size would increase by repeated cell divisions done
clear
B)
Root initiation would take place done
clear
C)
Shoot initiation would occur done
clear
D)
The callus would die done
clear
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question_answer 7)
Moving on a grass lawn facilitates better maintenance primarily owing to [CBSE PMT 1989; JIPMER 1994]
A)
Removal of apical dominance and promotion of lateral meristem done
clear
B)
Removal of apical dominance done
clear
C)
Wounding which stimulate rapid regeneration done
clear
D)
None of the above done
clear
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question_answer 8)
Apical dominance means [CPMT 1989]
A)
Suppression of growth of apical bud by axillary buds done
clear
B)
Suppression of growth of axillary buds by presence of apical bud done
clear
C)
Stimulation of growth of apical bud by removal of axillary buds done
clear
D)
Inhibition of growth of axillary buds by removal of apical bud done
clear
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question_answer 9)
A plant placed near a window bends outwards because [CPMT 1989]
A)
Its tip is able to get more oxygen done
clear
B)
Its tip is able to obtain more light done
clear
C)
Its tip is able to receive necessary warmth done
clear
D)
The auxin contents on the shadow side is higher than that on the lighter side and as a result the shaded side elongate more than the cells on the illuminated side and the tip bends outwards done
clear
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question_answer 10)
Which of the following statement is false with respect to application of auxins [BHU 1989]
A)
Control direction of growth of plants done
clear
B)
Inhibits lateral bud growth done
clear
C)
Initiate and promote cell division actively particularly in tissue culture done
clear
D)
Produce hyperelongation effect done
clear
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question_answer 11)
A green plant bends towards the source of light when exposed to the light on only one side, it bends towards the source of light as it grows. Which of the following is the best explanation of the phenomenon [AFMC 1981; BHU 1984; CPMT 1977, 84, 88]
A)
The apices of their stems are attracted by light done
clear
B)
They need light for photosynthesis done
clear
C)
Some auxins accumulates on the shaded side to induce greater cell elongation on that side done
clear
D)
Light stimulates the cells on the illuminated side to increase in length done
clear
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question_answer 12)
Which arrangement of an agar block on an oat coleoptile would result in IAA collecting in the agar
A)
B)
C)
D)
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question_answer 13)
Exogenous application of gibberellins induces male flower formation on genetically female plants in [AIIMS 1986]
A)
Carica done
clear
B)
Cucumis done
clear
C)
Coccinia done
clear
D)
Cucurbita done
clear
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question_answer 14)
A genetically dwarf plant can be converted into a tall plant by the use of [MP PMT 1996]
A)
Kinetin done
clear
B)
\[G{{A}_{3}}\] done
clear
C)
IAA/X-rays done
clear
D)
2, 4-D done
clear
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question_answer 15)
Went (1928) reported that auxin moves from apical to basal end i.e., basipetally the movement is quite fast, in root is about
A)
0 to 1 cm/h done
clear
B)
0.1 to 0.2 cm/h done
clear
C)
0.2 to 0.3 cm/h done
clear
D)
0.3 to 0.4 cm/h done
clear
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question_answer 16)
The ripening of fruits can be accelerated by [DPMT 1979, 85]
A)
Reducing the supply of water to plant when fruits are maturing done
clear
B)
Increasing the supply of nitrogen to the atmosphere surrounding them done
clear
C)
Warming up the surroundings artificially done
clear
D)
Artificially adding ethylene gas to the atmosphere surrounding them done
clear
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question_answer 17)
Abscisic acid is an antitranspirant. It prevents transpiration by
A)
Forming a film impervious to water over the stomata done
clear
B)
Preventing K+ ion uptake, thus decreasing the osmotic concentration of the guard cells and keeping them flaccid done
clear
C)
Inducing starch formation, thus decreasing the osmotic concentration of the guard cells and keeping them flaccid done
clear
D)
Increasing respiration, thus increasing\[C{{O}_{2}}\]concentration in the guard cells which helps in keeping the guard cells flaccid done
clear
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question_answer 18)
The relation of flowering to the lengths of light and dark period was investigated by two experiments. In one experiment, the plants were subjected to dark periods of various lengths while the light periods were kept at 4 hours. In the second experiment, plants were kept in dark periods of various lengths while the light periods were kept at 16 hours. The number of flowers formed in relation to these periods is shown in the table
Dark periods hours
flowers formed in experimental light periods
4 hours
16 hours
8
0
0
10
0
0
12
4
6
14
5
7
16
5
8
These results indicate that flowering
A)
Requires long days done
clear
B)
Is initiated by a long light period done
clear
C)
Is due to short light periods done
clear
D)
Requires a minimum dark period done
clear
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question_answer 19)
When all parts except the leaves of a short day plant are covered with a light-proof cover and then subjected to short day light/dark treatment, it will produce flower buds. When a portion of this plant is grafted on to another plant of the same species which has been prevented from flowering by excessive exposure to light, this latter plant will also produce flower buds. Which is the best inference from this result
A)
Hormones can transmit information to all parts of plants done
clear
B)
Leaves are more sensitive to the photoperiodic stimulus than other parts of the plant done
clear
C)
The photoperiodic stimulus is received by the leaves and transmitted by a hormone done
clear
D)
The photoperiodic stimulus is received by all parts of the shoot and transmitted by a hormone done
clear
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question_answer 20)
Which one of the following statements is true for the phytochrome [MP PMT 1995]
A)
Phytochrome is a phytohormone done
clear
B)
Phytochrome is a photosynthetic pigment done
clear
C)
Phytochrome is a pigment that controls growth, photomorphogenesis and development of many plants done
clear
D)
Phytochrome is a regulatory protein that controls several dark-dependent developmental processes done
clear
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question_answer 21)
A short-day plant was exposed to alternating red-far red treatments. What would happen if the last treatment was of far-red light
A)
Flowering would occur done
clear
B)
Flowering would not occur done
clear
C)
Plant would etiolate done
clear
D)
Plant would die done
clear
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question_answer 22)
What will be the effect on phytochrome in a plant subjected to continuous red light [CBSE PMT 1997]
A)
Level of phytochrome will decrease done
clear
B)
Phytochrome will be destroyed done
clear
C)
Phytochrome synthesis will increase done
clear
D)
None of these done
clear
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question_answer 23)
Clinostat is the apparatus used to [MP PMT 1990]
A)
Measure the rate of growth in plant done
clear
B)
Measure the quantity of auxin in plant done
clear
C)
Measure the effect of light on plant done
clear
D)
Eliminate the effect of gravity on plant done
clear
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question_answer 24)
Sleep movements of leaves in certain plants are or photo nasty is due to [DPMT 1985]
A)
Excess of transpiration done
clear
B)
The leaves getting tired of carrying on photosynthesis done
clear
C)
Decrease in the intensity of light done
clear
D)
Differential growth at the base of leaf done
clear
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question_answer 25)
What causes a green plant to bend towards light as it grows [CPMT 1973, 84]
A)
Because green plants need light to carry on photosynthesis done
clear
B)
Because green plants are phototropic done
clear
C)
Light stimulates, plant cells on the lighted side to grow faster done
clear
D)
Auxin accumulates on shaded side stimulating greater cell elongation done
clear
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