MCQGeeks
0 : 0 : 1
CBSE
JEE
NTSE
NEET
English
UK Quiz
Quiz
Driving Test
Practice
Games
NEET
NEET Biology MCQ
Neet Botany Plant Growth And Movements Mcq
Quiz 1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Q.1
Name the plant growth regulator which upon spraying on sugarcane crop, increases the length of stem, thus increasing the yield of sugarcane crop. [NEET 2020]
0%
a) Ethylene
0%
b) Abscisic acid
0%
c) Cytokinin
0%
d) Gibberellin
Explanation
Answer : (d)
Q.2
Thiobacillus is a group of bacteria helpful in carrying out .... [NEET 2019]
0%
a) Nitrogen fixation
0%
b) Chemoautotrophic fixation
0%
c) Nitrification
0%
d) Denitrification
Explanation
Thiobacillus denitrificans is a chemoautotrophic microorganism which is able to denitrify utilizing sulphides as electron donors. Its presence resulted in a high denitrification rate, oxidizing sulphide to sulphate, and reducing nitrate to nitrogen gas. Answer : (d)
Q.3
What is the site of perception of photoperiod necessary for induction of flowering in plants? [NEET 2019]
0%
a) Lateral buds
0%
b) Pulvinus
0%
c) Shoot apex
0%
d) Leaves
Explanation
During flowering, photoperiodic stimulus is perceived by leaves of plants Answer : (d)
Q.4
It takes very long time for pineapple plants to produce flowers. Which combination of hormones can be applied to artificially induce flowering in pineapple plants throughout the year to increase yield?
0%
a) Auxin and Ethylene
0%
b) Gibberellin and Cytokinin
0%
c) Gibberellin and Abscisic acid
0%
d) Cytokinin and Abscisic acid
Explanation
Plant hormone auxin induces flowering in pineapple. Ethylene also helps in synchronization of flowering and fruit set up in pineapple. Answer : (a)
Q.5
Which of the following is not an inhibitory substance governing seed dormancy? (1) (2) (3) (4) Answer (3)
0%
a) Phenolic acid
0%
b) Para-ascorbic acid
0%
c) Gibberellic acid
0%
d) Abscisic acid
Explanation
Answer : (c)
Q.6
Bulliform cells in Grass leaves show ... .... [ AIIMS 1996]
0%
a) Growth movements
0%
b) Tropic movements
0%
c) Nastic movements
0%
d) Turgor movements
Explanation
The important functions of bulliform cells are: It is mainly concerned with storage of water. During the water stress condition in leaf minimize by curling the leaf inwards. It is concerned with the rolling and unrolling of the leaves (Turgor movement). Answer : (d)
Q.7
Opening of flower and drooping of bud are ... ... [ BHU 2007]
0%
a) Hyponasty
0%
b) Epinasty
0%
c) Curvature movement
0%
d) Spontaneous movements
Explanation
Definition of epinasty. : a nastic movement in which a plant part (such as a flower petal) is bent outward and often downward. Hyponasty an upward bending of leaves or other plant parts, caused by increased growth on their lower surface. The movements which allow organs of plants to move in or the other direction is called movements of curvature. These movements are of two types i.e. mechanical (found in non living organs of plant) and another is vital movements (found in living organs of plants) Answer : (b)
Q.8
The name zeatin was coined by ... ... [ RPMT 1995]
0%
a) Skoog
0%
b) Miller
0%
c) Letham
0%
d) Melvin
Explanation
Zeatin is a natural cytokinin first isolated from maize. It is an adenine derivative. The name zeatin was coined by Letham. It stimulates cell division Answer : (c)
Q.9
Ability of Venus Fly Trap to capture insects is due to ... .... [ CBSE 2005]
0%
a) Specialised "muscle-like" cells
0%
b) Chemical stimulation by prey
0%
c) Rapid turgor pressure changes
0%
d) Passive process requiring no special ability on the apart of the pant
Explanation
When an insect touches these hairs, this stimulus causes rapid turgor pressure changes which closes the leaf. Answer : (c)
Q.10
In a plant subjected to continuous red light phytochrome will show ... ... [ CBSE 1997]
0%
a) Increased synthesis
0%
b) Decreased level
0%
c) Destruction
0%
d) Destruction and synthesis remain in balance
Explanation
The phytochrome molecule is the photoreceptor for red light responses. It exists in two forms, Pr and Pfr Pfr is the physiologically-active form of the protein; exposure to red light yields physiological activity in the plant. Exposure to far-red light converts the Pfr to the inactive Pr form, inhibiting phytochrome activity. Together, the two forms represent the phytochrome system If, we subject a plant to continuous red light, the level of phytochrome in the plant decrease below a critical value and triggers the de novo synthesis of more phytochromes in the Pr form. The result is an equilibrium in the plant between the synthesis and the destruction of phytochrome Answer : (d)
Q.11
Who first suggested presence of growth regulatory chemicals in plants? ... ...[ MPPMT 2001]
0%
a) Went
0%
b) Sachs
0%
c) Darwin
0%
d) Paal
Explanation
Frits Warmolt Went was among the first to demonstrate the importance of hormones in plant growth and development. in 1928 experiment he demonstrated the existence of auxin in plants. Where as Charles Darwin was among the first scientists to dabble in plant hormone research. In his book "The Power of Movement in Plants" presented in 1880, he first describes the effects of light on movement of canary grass (Phalaris canariensis) coleoptiles. Answer : (a)
Q.12
2,4-D causes ... ... [ CPMT 1996]
0%
a) Delay in senescence
0%
b) Bolting
0%
c) Increase in branches
0%
d) Increased growth of all parts
Explanation
Search Results Web results 2,4-Dichlorophenoxyacetic Acid (2,4-D) acts as a plant growth promoter while at higher doses it induces symptoms in plants similar to those induced by higher doses of auxin (IAA). Answer : (d)
Q.13
Environmental rhythms of light and darkness produce ... ... [ CBSE 1998]
0%
a) Photoperiodism
0%
b) Phototropism
0%
c) Phototaxis
0%
d) Vernalisation
Explanation
Photoperiodism is the physiological reaction of organisms to the length of night or a dark period. Answer : (a)
Q.14
Which one is used for defoliation of forest trees? ... ... [ CBSE 1998]
0%
a) Phosphon D
0%
b) Maleic hydrazide
0%
c) AMO 1618
0%
d) 2, 4-D
Explanation
2,4-D (2,4 dichlorophenoxy acetic acid) is an auxin hormone. It over stimulates the growth activities of the cells of the root due to which roots get destroyed and thus plants finally destroyed Answer : (d)
Q.15
Statement a: Auxins promote apical dominance by suppressing activity of lateral buds Statement b: In moriculture, periodic pruning of shoot tips is done to makes Mulberry plants bushy
0%
a) a and b correct with a being reason for b
0%
b) a is correct, b is wrong
0%
c) a is wrong, b is correct
0%
d) Both a and b correct but a is not reason for b
Explanation
Auxin is produced by shoot tip and acts as a growth promoter for apical bud and inhibit the growth of lateral buds. When a terminal bud is removed, the nearest axillary buds begin to grow and the plant branches rapidly. In case of mulberry plants, pruning is done to remove apical dominance and cause more branching of the main body of the plant. Answer : (a)
Q.16
Which of the following stimulates growth or call enlargement? ... ... [ Pb PMT 1997]
0%
a) Gibberellin
0%
b) Auxin
0%
c) Cytokinin
0%
d) Ethylene
Explanation
Auxin is a plant hormone produced in the stem tip that promotes cell elongation. Answer : (b)
Q.17
Treatment of seeds at low temperature under moist conditions for breaking their dormancy is ... ... [ AFMC 2008] Explanation is provided click on
0%
a) Vernalisation
0%
b) Chelation
0%
c) Stratification
0%
d) Scarification
Explanation
Stratification involves the treatment of seed at low temperature ( 5-10°) under sufficiently moist conditions to break its dormancy and to induce germination. Scarification involves any damage or breakage of seed coat by physical methods (e.g., Use of scalpel, wooden hammer etc.) or chemical methods (use of mild acids) to break seed dormoney. Vernalization and Chelation is the chill treatment of plant in its early stages of life history to stimulate or induce early flowering. Answer : (c)
Q.18
Biennials get changed into annuals by ... ... [ MHTCET 2010]
0%
a) Hormones
0%
b) Photoperiodism
0%
c) Grafting
0%
d) Vernalisation
Explanation
Biennial plants are changed into annual plants by the process of vernalisation and induces flowering Answer : (d)
Q.19
Pigment involved in regulation/photomorphogenesis response is ... ... [ BHU 2001]
0%
a) Phytochrome
0%
b) Cytochrome
0%
c) Xanthophyll
0%
d) Chlorophyll b
Explanation
Phytochrome is a plant pigment that is involved in the initiation and regulation of photoperiodism and photomorphogenesis. Phytochromes absorb red and far-red light and signals for a photomorphogenetic response. Answer : (a)
Q.20
Parthenocarpic fruit cannot be produced by application of ... ... [ Manipal 2004]
0%
a) IAA
0%
b) 2,4-D
0%
c) ABA
0%
d) IBA
Explanation
Parthenocarpy is the production of fruits without the fertilisation of ovules Hormones, auxins, gibberellins, and cytokinins, especially the first two, are well known to induce parthenocarpy. Thus, auxin treatment of young, unpollinated ovaries in certain cultivars of strawberry, tomato, grape, and orange is known to cause production of parthenocarpic fruit. Answer : (c)
Q.21
Flash of light in dark inhibits flowering in ... ..... [ AIIMS 1997]
0%
a) SDP
0%
b) LDP
0%
c) LSDP
0%
d) DNP
Explanation
Short day plant needs short-light period and uninterrupted long night period and a flash of light in dark inhibits flowering in short day plant (SDP). LDP or Long Day Plants flower when the days are longer. Light period is very critical in these plants.LSDP are Lond Day Short Plants.DNP stands for 2, 4- Dinitrophenol. Answer : (a)
Q.22
Growth in length is measured with the help of ... ... [ AFMC 2010]
0%
a) Manometer
0%
b) Auxanometer
0%
c) Potometer
0%
d) Clinostat
Explanation
An auxanometer is an apparatus for measuring increase of growth in plants. Answer : (b)
Q.23
Photoperiodism is probably due to synthesis of ... ... [ AMCE 1993]
0%
a) Cytokinins
0%
b) Gibberellins
0%
c) Auxin
0%
d) Florigen
Explanation
Florigen (or flowering hormone) is the hypothesized hormone-like molecule, florigen is an understanding of how plants use seasonal changes in day length to mediate flowering—a mechanism known as photoperiodism. Plants which exhibit photoperiodism may be either 'short day' or 'long day' plants, which in order to flower require short days or long days respectively, although plants in fact distinguish day length from night length Answer : (d)
Q.24
Skototropism movements are induced by ... ... [ BHU 1998 ]
0%
a) Night
0%
b) Light
0%
c) Touch
0%
d) Heat
Explanation
Skototropism Growth or movement away from light. Answer : (a)
Q.25
Assertion: Plant growth as a whole is indefinite Reason: Plants retain the capacity of continuous growth throughout their life ..... .... [ AIIMS 2011]
0%
a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion
0%
b) The Assertion and Reason are true but Reason is not correct explanation of Assertion
0%
c) Assertion is true but, Reason is false
0%
d) Assertion is false but, Reason is true
Explanation
Answer : (a)
Q.26
Which one of the following is a natural growth inhibitor? ... .. [ BHU 1999 ]
0%
a) NAA
0%
b) ABA/Ethylene
0%
c) IAA
0%
d) GA
Explanation
Hormones like Abscisic Acid (ABA), ethylene are growth inhibitor. These hormones accelerate abscission process and are involved in inhibition of growth. Naphthaleneacetic acid (NAA) is a synthetic auxin hormone that promotes growth. Indole Acetic Acid (IA). Auxin is a plant hormone produced in the stem tip that promotes cell elongation. Auxin moves to the darker side of the plant, causing the cells there to grow larger than corresponding cells on the lighter side of the plant. Answer : (b)
Q.27
Highest auxin concentration occurs .... ... [ CBSE 1990]
0%
a) In growing tips
0%
b) In leaves
0%
c) At base of plant organs
0%
d) In xylem and phloem
Explanation
Auxin is a plant hormone produced in the stem tip that promotes cell elongation. Auxin is highest at the tip — promoting the production of new cells at the meristem, and lowest in the region of differentiation — promoting the elongation and differentiation of root cells. Answer : (a)
Q.28
A green plant will turn yellow if placed in the dark. This is called ... ..[ CET Chd 2009]
0%
a) Phototropism
0%
b) Dormancy
0%
c) Chlorosis
0%
d) Etiolation
Explanation
Etiolation is a process in flowering plants grown in partial or complete absence of light. It is characterized by long, weak stems; smaller leaves due to longer internodes; and a pale yellow color (chlorosis). Answer : (d)
Q.29
Auxins are mostly produced in .... ... [ Manipur 2006]
0%
a) Shoot
0%
b) Meristematic region of stem
0%
c) Root
0%
d) Leaf buds
Explanation
Auxins promote stem elongation, inhibit growth of lateral buds (maintains apical dominance). They are produced in the stem, buds, and root tips. Auxin is a plant hormone produced in the stem tip that promotes cell elongation. Answer : (b)
Q.30
Growth hormone that speeds up malting in brewery industry is ... .... [ AMU 2012]
0%
a) Kinetin
0%
b) Gibberellic acid
0%
c) Auxin
0%
d) Ethylene
Explanation
Gibberellic acid is a plant growth regulator, which can improve the quality of malts when used in the malting process, which could speed up barley germination in the brewing industry Answer : (b)
Q.31
Growth hormones connected with bolting are ... ...[ BHU 1997]
0%
a) Cytokinins
0%
b) Auxins
0%
c) Coumarins
0%
d) Gibberellins
Explanation
Bolting is when agricultural and horticultural crops prematurely produce a flowering stem before the crop is harvested, in a natural attempt to produce seeds and hence reproduce. Bolting is induced by plant hormones of the gibberellin family,[citation needed] and can occur as a result of several factors, including changes in day length, the prevalence of high temperatures at particular stages in a plant's growth cycle, and the existence of stresses such as insufficient water or minerals. Answer : (d)
Q.32
What is true about phytochrome? ... ..... [ AIIMS 2001]
0%
a) Pr absorbs red light and becomes Pfr
0%
b) Pfr absorbs yellow light and becomes Pfr
0%
c) Pfr absorbs yellow light and becomes Pr
0%
d) Pfr absorbs red light and becomes Pr
Explanation
Phytochromes have two photo-interconvertible forms: Pr and Pfr. Pr absorbs red light (~667 nm) and is immediately converted to Pfr. Pfr absorbs far-red light (~730 nm) and is quickly converted back to Pr. Answer : (a)
Q.33
Hormone produced during leaf fall is ... ... [CPMT 2008]
0%
a) Cytokinin
0%
b) Florigen
0%
c) ABA
0%
d) IAA
Explanation
Abscisic acid (ABA) is often referred to as a inhibitory rather than stimulatory hormone. It is involved in the closure of stomata, bud and seed dormancy and is known to inhibit other hormonal actions. It triggers fall of mature leaves and fruits from plants Answer : (c)
Q.34
Parthenocarpic fruit can be produced by application of auxin ... ..... [ EAMCET 1999]
0%
a) IAA
0%
b) IBA
0%
c) NAA
0%
d) All the above
Explanation
Hormones, auxins, gibberellins, are well known to induce parthenocarpy. Five naturally occurring (endogenous) auxins in plants include indole-3-acetic acid (IAA) , 4-chloroindole-3-acetic acid, phenylacetic acid, indole-3-butyric acid (IBA), and indole-3-propionic acid. Synthetic auxin analogs include 1-naphthaleneacetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-D), and many others. Answer : (d)
Q.35
Cytokinin ... ... [ DPMT 1997]
0%
a) Is a hormone whose main function is the induction of cell division
0%
b) Is the process of cell division
0%
c) Refers to cell movements
0%
d) Causes dormancy
Explanation
cytokinins influence plant growth, development and physiology, including cell division, chloroplast differentiation and delay of senescence, the interaction with other organisms, including pathogens Answer : (a)
Q.36
Auxanometer is required for ... ... [ BHU 2007]
0%
a) Studying rate of transpiration
0%
b) Measuring rate of respiration
0%
c) Finding out rate of photosynthesis
0%
d) Calculating rate of growth
Explanation
An auxanometer is an apparatus for measuring increase of growth in plants. Answer : (d)
Q.37
Abscisic acid controls ... .... [ CBSE 1990]
0%
a) Cell division
0%
b) Leaf fall and dormancy
0%
c) Shoot elongation
0%
d) Cell elongation and wall formation
Explanation
Under stress, abscisic acid accumulates in plants, inhibiting stem elongation and inducing bud dormancy. The plant hormone ethylene controls fruit ripening, flower wilting, and leaf fall by stimulating the conversion of starch and acids to sugars. Abscisic acid is a sesquiterpene, which has important roles in seed development and maturation, in the synthesis of proteins and compatible osmolytes, which enable plants to tolerate stresses due to environmental or biotic factors, and as a general inhibitor of growth and metabolic activities. Answer : (b)
Q.38
IAA was first isolated from ... ... [CPMT 1990]
0%
a) Corn germ oil
0%
b) Gibberella
0%
c) Human urine
0%
d) Rhizopus
Explanation
Auxin, indole-3-acetic acid (IAA) was then isolated first from human urine, then from fungi, and finally from higher plants Answer : (c)
Q.39
Stomatal closure under stress conditions is due to ... .. [ Guj CET 2007]
0%
a) IAA
0%
b) ABA
0%
c) IBA
0%
d) 2, 4-D
Explanation
ABA binds to receptors at the surface of the plasma membrane of the guard cells that triggers closing of the stomata when soil water is insufficient to keep up with transpiration. Answer : (b)
Q.40
Drooping of Tamarind leaves after sunset is ... ... [ HPPMT 2007]
0%
a) Phototropism
0%
b) Phototaxis
0%
c) Photonasty
0%
d) Chemotaxis
Explanation
Photonasty a nastic movement that is associated with changes in light. intensity Nyctinastic movements are associated with diurnal light and temperature changes and controlled by the circadian clock and the light receptor phytochrome. Answer : (c)
Q.41
Example of positive geotropism is ... .... [ Odisha 1997]
0%
a) Closing of flowers
0%
b) Upward growth of stem
0%
c) Downward growth of root
0%
d) Lateral growth of root
Explanation
Geotropism is the growth of the parts of plants in response to the force of gravity. The upward growth of plant shoots is an instance of negative geotropism ; the downward growth of roots is positive geotropism. Answer : (c)
Q.42
One hormone helps in ripening of fruits and other brings about stomatal closure. They are respectively ... ... [ kerala 2008]
0%
a) ABA, IAA
0%
b) C2H4, ABA
0%
c) ABA, ethylene
0%
d) C2H4, GA
Explanation
Ethylene (C2H4) is a gas and is known as the “fruit-ripening hormone.” Every fruit has a certain level of ethylene production throughout its lifecycle. However, in some fruits, ethylene levels shoot up when the fruit starts ripening. Abscisic acid (ABA) is often referred to as a inhibitory rather than stimulatory hormone. It is involved in the closure of stomata, bud and seed dormancy and is known to inhibit other hormonal actions. It triggers fall of mature leaves and fruits from plants Answer : (b)
Q.43
Some flowers ( e.g. Oxalis) open in the morning and close during evening because of ... .... [ AIIMS 1996]
0%
a) Photonasty
0%
b) Phototropism
0%
c) Phototaxis
0%
d) Nyctinasty
Explanation
Photonasty a nastic movement that is associated with changes in light. intensity Nyctinastic movements are associated with diurnal light and temperature changes and controlled by the circadian clock and the light receptor phytochrome. Answer : (a)
Q.44
Geotropic response is perceived by .... ... [ DPMT 2001]
0%
a) Mature roots
0%
b) Elongating cells
0%
c) Root cap
0%
d) Root hairs
Explanation
Gravity is sensed in the root tip and this information then be relayed to the elongation zone Answer : (c)
Q.45
Each meristem influences other meristems. The phenomenon is ... ...[ AMU 2002]
0%
a) Allometry
0%
b) Growth correction
0%
c) Lag phase
0%
d) Auxetic growth
Explanation
The phenomenon in which each meristem influences other meristems is called as growth correction. Answer : (b)
Q.46
Pigment taking part in photo-perception in flowering is ... ... [ BHU 1991]
0%
a) Carotene
0%
b) Phytochrome
0%
c) Cytochrome
0%
d) Lycopene
Explanation
Phytochromes are a class of photoreceptor in plants, bacteria and fungi used to detect light. Phytochrome regulate the timing of flowering in adult plants and regulate the germination of seeds (photoblasty), the synthesis of chlorophyll, the elongation of seedlings, the size, shape and number and movement of leaves . Answer : (b)
Q.47
The phenomenon which shortens vegetative period and hastens flowering is ... ...
0%
a) Etiolation
0%
b) Vernalisation
0%
c) Photoperiodism
0%
d) Parthenocarpy
Explanation
Vernalisation the induction of a plant's flowering process, it is cooling of seed during germination in order to accelerate flowering when it is planted. Answer : (b)
Q.48
Which wavelengths are the most effective in photoperiodism? ... ..[ MPPMT 2011]
0%
a) Green and yellow
0%
b) Blue and red
0%
c) Blue and violet
0%
d) Red and far-red
Explanation
Many flowering plants (angiosperms) use a photoreceptor protein, such as phytochrome or cryptochrome, to sense seasonal changes in night length, or photoperiod, The phytochromes also differ in their absorption spectrum; that is, which wavelengths (e.g., red vs. far-red) they absorb best. Answer : (d)
Q.49
Which response of growth hormones is true for ethylene? ... .. [ MPPMT 1995]
0%
a) Decrease in flower abscission
0%
b) Decreases in femaleness
0%
c) Increase in fruit ripening
0%
d) Increase in cell elongation
Explanation
The plant hormone ethylene plays a key role in climacteric fruit ripening. The means by which ethylene selects the ripening-related genes and interacts with other signaling pathways to regulate the ripening process are still to be elucidated. Answer : (c)
Q.50
Match the columns ... ... [ kerala 2005]
a)Auxin
i) Colouring test in lemon
b) Gibberellin
ii) Cell division test in plants
c) Cytokinin
iii) Avena curvature test
d) Ethylene
iv) Dwarf corn test
0%
a) a - iii, b - iv, c - ii, d - i
0%
b) a - i, b - iv, c - ii, d - iii
0%
c) a - iv, b- iii, c - i, d - ii
0%
d) a - ii, b - i, c - iv, d - iii
Explanation
The Avena geo-curvature test is a bioassay for auxin-type growth regulators. a - iii, Gibberellin bioassay is performed through dwarf pea and maize test. b - iv, Cytokinins are a particular type of plant hormone that are involved in regulation of cell proliferation, cell cycle progression, and cell and plastid development c - ii, Colouring test of lemon is based on the property of ethylene in inducing ripening. d - i Answer : (a)
0 h : 0 m : 1 s
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Report Question
×
What's an issue?
Question is wrong
Answer is wrong
Other Reason
Want to elaborate a bit more? (optional)
Support mcqgeeks.com by disabling your adblocker.
×
Please disable the adBlock and continue.
Thank you.
Reload page