71. Wheat, potato and henbane are

A SDP
B DNP
C LNP
D LDP
Answer :   LDP
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72. Auxanometer is meant for measuring

A Respiratory activity
B Photosynthetic activity
C Growth activity
D Osmotic pressure
Answer :   Growth activity
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73. Gibbereling was isolated from

A An alga
B A fungus
C A bacterium
D A virus
Answer :   A fungus
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74. Long day plant's produces flowers when they exposed to

A Any duration of light
B Light period longer than a critinal day lenght
C Light period longer than 12 hrs.
D None of the above
Answer :   Light period longer than a critinal day lenght
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75. The regulator which retards ageing/senescence of plant parts is :

A cytokinin
B auxin
C gibberellin
D abscisic acid
Answer :   cytokinin
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76. The hormone responsible for apical dominance is

A IAA
B GA
C ABA
D florigen
Answer :   IAA
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77. The clasical experiments on growth were performed by

A Lamarck and Boysen Tansen
B Boysen Jansen and Darwin
C Darwin and Lamarck
D Devries and Paal
Answer :   Boysen Jansen and Darwin
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78. What causes a green plant to bend towards light as it grows

A Because green plants need light to carry on photosynthesis
B Because green plants are phototropic
C Light stimulates plant cells on the lighted side to grow faster
D Auxin accumulates on the shaded side
Answer :   Auxin accumulates on the shaded side
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79. Which one increases in the absence of light?

A Uptake of minerals
B Uptake of water
C Elongation of internodes
D Ascent of sap
Answer :   Elongation of internodes
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80. Growth hormone acts

A Always as growth promotors
B Always are growth inhibitors
C Some as promotors and some as inhibitors
D Rarely as growth inducers
Answer :   Some as promotors and some as inhibitors
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