2010
Q51
NEET
MCQ
10 Mar 2026
Root development is promoted by
A.
abscisic acid
B.
auxin
C.
gibberellin
D.
ethylene.
2010
Q52
NEET
MCQ
10 Mar 2026
Phototropic curvature is the result of uneven distribution of
A.
gibberellin
B.
phytochrome
C.
cytokinins
D.
auxin.
2010
Q53
NEET
MCQ
10 Mar 2026
Coiling of garden pea tendrils around any support is an example of
A.
thigmotaxis
B.
thigmonasty
C.
thigmotropism
D.
thermotaxis.
2010
Q54
NEET
MCQ
10 Mar 2026
Photoperiodism was first characterised in
A.
tobacco
B.
potato
C.
tomato
D.
cotton.
2009
Q55
NEET
MCQ
10 Mar 2026
Which one of the following acids is a derivative of carotenoids?
A.
Indole-3-acetic acid
B.
Gibberellic acid
C.
Abscisic acid
D.
Indole butyric acid
2009
Q56
NEET
MCQ
10 Mar 2026
One of the synthetic auxin is
A.
IAA
B.
GA
C.
IBA
D.
NAA
2008
Q57
NEET
MCQ
10 Mar 2026
Senescence as an active developmental cellular process in growth and functioning of a flowering plant, is indicated in
A.
annul plants
B.
floral parts
C.
vessels and tracheid differentiation leaf abscission.
D.
leaf abscission.
2008
Q58
NEET
MCQ
10 Mar 2026
Importance of day length in flowering of plants was first shown in
A.
cotton
B.
Petunia
C.
Lemna
D.
tobacco.
2007
Q59
NEET
MCQ
10 Mar 2026
Which one of the following pairs, is not correctly matched?
A.
Gibberellic acid - Leaf fall
B.
Cytokinin - Cell division
C.
IAA - Cell wall elongation
D.
Abscissic acid - Stomatal closure
2007
Q60
NEET
MCQ
10 Mar 2026
The wavelength of light absorbed by Pr form of phytochrome is
A.
680 nm
B.
720 nm
C.
620 nm
D.
640 nm.
2007
Q61
NEET
MCQ
10 Mar 2026
Opening of floral buds into flowers, is a type of
A.
autonomic movement of variation
B.
paratonic movement of growth
C.
autonomic movement of growth
D.
autonomic movement of locomotion.
2006
Q62
NEET
MCQ
10 Mar 2026
Treatment of seeds at low temperature under moist conditions to break its dormancy is called
A.
stratification
B.
scarification
C.
vernalization
D.
chelation.
2006
Q63
NEET
MCQ
10 Mar 2026
An enzyme that can stimulate germination of barley seeds is
A.
invertase
B.
$\alpha $-amylase
C.
lipase
D.
protease
2006
Q64
NEET
MCQ
10 Mar 2026
How does pruning help in making the hedge dense?
A.
It releases wound hormones.
B.
It induces the differentiation of new shoots from the rootstock.
C.
It frees axillary buds from apical dominance.
D.
The apical shoot grows faster after pruning.
2006
Q65
NEET
MCQ
10 Mar 2026
Farmers in a particular region were concerned that pre-mature yellowing of leaves of a pulse crop might cause decrease in the yield. Which treatment could be most beneficial to obtain maximum seed yield?
A.
Application of iron and magnesium to promote synthesis of chlorophyll
B.
Frequent irrigation of the crop
C.
Treatment of the plants with cytokinins along with a small does of nitrogenous fertilizer
D.
Removal of all yellow leaves and spraying the remaining green leaves with 2, 4, 5-trichlorophhenoxy acetic acid
2005
Q66
NEET
MCQ
10 Mar 2026
The ability of the Venus Flytrap to capture insects is due to
A.
specialized ''muscle-like'' cells
B.
chemical stimulation by the prey
C.
a passive process requiring no special ability on the part of the plant
D.
rapid turgor pressure changes.
2004
Q67
NEET
MCQ
10 Mar 2026
Cell elongation in internodal regions of the green plants takes place due to
A.
indole acetic acid
B.
cytokinins
C.
gibberellins
D.
ethylene.
2004
Q68
NEET
MCQ
10 Mar 2026
One set of the plant was grown at 12 hours day and 12 hours night period cycles and it flowered while in the other set night phase was interrupted by flash of light and it did not produce flower. Under which one of the following categories will you place this plant?
A.
Long day
B.
Darkness neutral
C.
Day neutral
D.
Short day
2003
Q69
NEET
MCQ
10 Mar 2026
Nicotiana sylvestris flowers only during long days and N.tabacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross-fertilized to produce self-fertile offspring. What is the best reason for considering N.sylvestris and N.tabacum to be separate species?
A.
They cannot interbreed in nature
B.
They are reproductively distinct
C.
They are physiologically distinct
D.
They are morphologically distinct
2003
Q70
NEET
MCQ
10 Mar 2026
Plants deficient of element zinc, show its effect on the biosynthesis of plant growth hormone
A.
auxin
B.
cytokinin
C.
ethylene
D.
abscisic acid.
2003
Q71
NEET
MCQ
10 Mar 2026
Differentiation of shoot is controlled by
A.
high auxin : cytokinin ratio
B.
high cytokinin : auxin ratio
C.
high gibberellin : auxin ration
D.
high gibberellin : cytokinin ratio.
2003
Q72
NEET
MCQ
10 Mar 2026
Coconut milk factor is
A.
abscisic acid
B.
an auxin
C.
a gibberellin
D.
cytokinin
2002
Q73
NEET
MCQ
10 Mar 2026
Dwarfness can be controlled by treating the plant with
A.
cytokinin
B.
gibberellic acid
C.
auxin
D.
antigibberellin.
2002
Q74
NEET
MCQ
10 Mar 2026
Seed dormancy is due to the
A.
ethylene
B.
abscisic acid
C.
IAA
D.
starch.
2001
Q75
NEET
MCQ
10 Mar 2026
Hormone responsible for senescence is
A.
ABA
B.
auxin
C.
GA
D.
cytokinin
2001
Q76
NEET
MCQ
10 Mar 2026
Which of the following prevents the fall of fruits?
A.
GA3
B.
NAA
C.
Ethylene
D.
Zeatin
2001
Q77
NEET
MCQ
10 Mar 2026
Which hormone breaks dormancy of potato tuber?
A.
Gibberellin
B.
IAA
C.
ABA
D.
Zeatin
2001
Q78
NEET
MCQ
10 Mar 2026
Which plant is LDP?
A.
Tobacco
B.
Glycine max
C.
Mirabilis jalapa
D.
Spinach
2000
Q79
NEET
MCQ
10 Mar 2026
If the apical bud has been removed then we observe
A.
more lateral branches
B.
more axillary buds
C.
plant growing stops
D.
flowering stops.
2000
Q80
NEET
MCQ
10 Mar 2026
By which action a seed coat becomes permeable to water
A.
scarification
B.
stratification
C.
vernalization
D.
all of the above.
2000
Q81
NEET
MCQ
10 Mar 2026
Which hormone is responsible for fruit ripening?
A.
Ethylene
B.
Auxin
C.
Ethyl chloride
D.
Cyctokinin