NEET Biology Plant Growth and Development MCQs Set B

Question: Which of the following statements does not characterize photoperiodism

• a) Red light is stimulatory in SDP, LDP and DNP for flowering
• b) Conversion of shoot apex into reproductive apex
• c) Mediated by florigen hormone
• d) Photoperiodic stimulus is perceived by mature leaf

Answer: Red light is stimulatory in SDP, LDP and DNP for flowering

Question: Hypothetical 'florigen' could be produced prematurely in long day plant by exposing it to

• a) Red light during night
• b) Far red light
• c) Shortening light period
• d) Extending dark period

Answer: Red light during night

Question: All given statements are correct w.r.t. photoperiodism, except

• a) Stimulus is received by young leaves
• b) Discovered by Garner and Allard in a variety of tobacco
• c) Florigen is the hypothetical hormone produced in response to stimulus
• d) Florigen is transported to bud through phloem

Answer: Stimulus is received by young leaves

Question: Which of the following pair is mismatched?

• a) Raphanus sativus - SLDP
• b) Zea mays - DNP
• c) Triticum aestivum - LDP
• d) Glycine max - SDP

Answer: Raphanus sativus - SLDP

Question: Which is not a requirement of vernalisation?

• a) Differentiated tissues
• b) Moisture
• c) Aerobic condition
• d) Low temperature

Answer: Differentiated tissues

Question:  Auxin can be bioassayed by

• a) Avena coleoptile curvature
• b) Potometer
• c) Lettuce hypocotyl elongation
• d) Hydroponics

Answer: Avena coleoptile curvature

Question: Typical growth curve in plants is

• a) Sigmoid
• b) Parabolic
• c) Linear
• d) Stair-steps shaped

Answer: Sigmoid

Question: What causes a green plant exposed to the light on only one side, to bend toward the source of light as it grows?

• a) Auxin accumulates on the shaded side, stimulating greater cell elongation there
• b) Green plants need light to perform photosynthesis
• c) Green plants seek light because they are phototropic
• d) Light stimulates plant cells on the lighted side to grow faster

Answer: Auxin accumulates on the shaded side, stimulating greater cell elongation there

Question: A few normal seedings of tomato were kept in a dark room. After a few days they were found to have become whitecoloured like albinos. Which of the following terms will you use to describe them?

• a) Etiolated
• b) Defoliated
• c) Embolised
• d) Mutated

Answer: Etiolated

Question: Which one of the following growth regulators is known as stress hormone?

• a) Abscissic acid
• b) Ethylene
• c) Indole acetic acid
• d) GA₃

Answer: Abscissic acid

Question: Dr.F. Went noted that if coleoptile tips were removed and placed on agar for one hour, the agar would produce a bending when placed on one side of freshly - cut coleoptile stumps. Of what significance is this experiment?

• a) It is the basis for quantitative determination of small amounts of growth-promoting substances
• b) It made possible the isolation and exact identification of auxin
• c) It supports the hypothesis that IAA is auxin
• d) It demonstrated polar movement of auxins

Answer: It is the basis for quantitative determination of small amounts of growth-promoting substances

Question: During seed germination its stored food is mobilized by

• a) Gibberellin
• b) Ethylene
• c) ABA
• d) Cytokinin

Answer: Gibberellin

Question: Through their effect on plant growth regulators, what do the temperature and light control in the plants?

• a) Flowering
• b) Apical dominance
• c) Closure of stomata
• d) Fruit elongation

Answer: Flowering

Question: Which one of the following generally acts as an antagonist to gibberellins?

• a) ABA
• b) IAA
• c) Ethylene
• d)Zeatin

Answer: ABA

Question: Vernalisation stimulates flowering in

• a) Carrot
• b) Ginger
• c) Turmeric
• d) Zamikand

Answer: Carrot

Question: Photoperiodism was first characterised in

• a) Tobacco
• b) Cotton
• c) Potato
• d) Tomato

Answer: Tobacco

Question: Phototropic curvature is the result of uneven distribution of

• a) Auxin
• b) Gibberellin
• c) Phytochrome
• d) Cytokinins

Answer: Auxin

Question: Coiling of garden pea tendrils around any support is an example of

• a) Thigmotropism
• b) Thigmonasty
• c) Thigmotaxis
• d) None of these

Answer: Thigmotropism

Question: One of the commonly used plant growth hormone is tea plantations is

• a) Indole-3-acetic acid
• b) Zeatin
• c) Abscisic acid
• d) Ethylene

Answer: Indole-3-acetic acid

Question: Root development is promoted by

• a) Ethylene
• b) Gibberellin
• c) Auxin
• d)Abscisic acid

Answer: Ethylene

Question: One of the synthetic auxin is

• a) NAA
• b) IBA
• c) GA
• d) IAA

Answer: NAA

Question: Which one of the following acids is a derivative of carotenoids?

• a) Abscisic acid
• b) Indole butyric acid
• c) Gibberellic acid
• d) Indole-3-acetic acid

Answer: Abscisic acid

Question: Senescence as an active developmental cellular process in the growth and functioning of a flowering plant, is indicated in

• a) Leaf abscission
• b) Floral parts
• c) Vessels and tracheid differentiation
• d) Annual plants

Answer: Leaf abscission

Question: Importance of day length in flowering of plants was first shown in

• a) Tobacco
• b) Cotton
• c) Lemna
• d) Petunia

Answer: Tobacco

Question: “Foolish Seedling” disease of rice led to the discovery of

• a) GA
• b) ABA
• c) 2, 4 – D
• d) IAA

Answer: GA

Question: Opening of floral buds into flowers, is type of:

• a) Autonomic movement of growth
• b) Autonomic movement of variation
• c) Paratonic movement of growth
• d) Autonomic movement of locomotion

Answer: Autonomic movement of growth

Question: Which one of the following pairs, is not correctly matched?

• a) Gibberellic acid – Leaf fall
• b) IAA – Cell wall elongation
• c) Abscissic acid – Stomatal closure
• d) Cytokinin – Cell division

Answer: Gibberellic acid – Leaf fall

Question: The wavelength of light absorbed by Pr form of phytochrome is

• a) 660 nm
• b) 720 nm
• c) 620 nm
• d) 640 nm

Answer: 660 nm

Question: How does pruning help in making the hedge dense?

• a) It frees axillary buds from apical dominance
• b) It induces the differentiation of new shoots from the rootstock
• c) The apical shoot grows faster after pruning
• d) It releases wound hormones

Answer: It frees axillary buds from apical dominance

Question: Treatment of seed at low temperature under moist conditions to break its dormancy is called

• a) Stratification
• b) Chelation
• c) Vernalization
• d) Scarification

Answer: Stratification

Question: An enzyme that can stimulate germination of barley seeds is

• a)

  

• b) Lipase
• c) Protease
• d) Invertase

Answer:

Question: 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) Treatment of the plants with cytokinins along with a small dose of nitrogenous fertilizer
• b) Frequent irrigation of the crop
• c) Removal of all yellow leaves and spraying the remaining green leaves with 2, 4, 5-trichlorophenoxy acetic acid
• d) Application of iron and magnesium to promote synthesis of chlorophyll

Answer: Treatment of the plants with cytokinins along with a small dose of nitrogenous fertilizer

Question: The ability of the venus flytrap to capture insects is due to

• a) Rapid turgor pressure changes
• b) Specialized “muscle-like” cells
• c) A passive process requiring no special ability on the part of the plant
• d) Chemical stimulation by the prey

Answer: Rapid turgor pressure changes

Question: The pineapple which under natural conditions is difficult to blossom has been made to produce fruits throughout the year by application of

• a) NAA, 2, 4-D
• b) Phenyl acetic acid
• c) Cytokinin
• d) IAA, IBA

Answer: NAA, 2, 4-D

Question: If the growing plant is decapitated, then

• a) Axillary buds are activated
• b) Axillary buds are inactivated
• c) Leaves become yellow and fall down
• d) Its growth stops

Answer:  Axillary buds are activated

Question: The movement of auxin is largely

• a) Basipetal
• b) Centripetal
• c) Acropetal
• d) None of these

Answer: Basipetal

Question: Which one among the following chemicals is used for causing defoliation of forest trees?

• a) 2, 4-D
• b) Malic hydrazide
• c) AMO-1618
• d) Phosphon D

Answer: 2, 4-D

Question: If the apical bud has been removed then we observe

• a) More lateral branches
• b) Plant growth stops
• c) More adventitious buds
• d) Flowering stops

Answer:  More lateral branches

Question: Which of the following prevents the fall of fruits?

• a) NAA
• b) Ethylene
• c) Zeatin
• d) GA₃

Answer: NAA

Question: Plants deficient of element zinc, show its effect on the biosynthesis of plant growth hormone

• a) Auxin
• b) Abscissic acid
• c) Cytokinin
• d) Ethylene

Answer: Auxin

Question: The maximum growth rate occurs in

• a) Exponential phase
• b) Lag phase
• c) Senescent phase
• d) Stationary phase

Answer: Exponential phase

Question: Gibberellic acid induces flower

• a) In long day plants under short day conditions
• b) In day-neutral plants under dark conditions
• c) In short day plants under long day conditions
• d) In some gymnospermic plants only

Answer: In long day plants under short day conditions

Question: Which breaks dormancy of potato tuber?

• a) Gibberellin
• b) IAA
• c) ABA
• d) Zeatin

Answer: Gibberellin

Question: Cell elongation in internodal regions of the green plants takes place due to

• a) Gibberellins
• b) Ethylene
• c) Cytokinins
• d) Indole acetic acid

Answer: Gibberellins

Question: Natural cytokinins are synthesized in tissues that are

• a) Dividing rapidly
• b) Storing food material
• c) Differentiating
• d) Senescent

Answer: Dividing rapidly

Question: Differentiation of shoot is controlled by

• a) High cytokinin : auxin ratio
• b) High gibberellin : cytokinin ratio
• c) High auxin : cytokinin ratio
• d) High gibberellin : auxin ratio

Answer:  High cytokinin : auxin ratio

Question: Coconut milk factor is

• a) Cytokinin
• b) Abscissic acid
• c) A Gibberellin
• d) Auxin

Answer: Cytokinin

Question:  Which combination of gases is suitable for fruit ripening?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which hormone is responsible for fruit ripening?

• a) Ethylene
• b) Auxin
• c) Ethyl chloride
• d) Cytokinin

Answer: Ethylene

Question: ABA is involved in

• a) Dormancy of seeds
• b) Root elongation
• c) Increased cell division
• d) Shoot elongation

Answer: Dormancy of seeds

Question: Hormone responsible for senescence

• a) ABA
• b) Auxin
• c) GA
• d) Cytokinin

Answer: ABA

Question: By which action a seed coat becomes permeable to water?

• a) Scarification
• b) Stratification
• c) Vernalization
• d) All of these

Answer:  Scarification

Question: The response of different organisms to the environmental rhythms of light and darkness is called

• a) Photoperiodism
• b) Vernalization
• c) Phototaxis
• d) Phototropism

Answer: Photoperiodism

Question: Which plant is LDP?

• a) Spinach
• b) Mirabilis jalapa
• c) Glycine max
• d) Tobacco

Answer: Spinach

Question: Proteinaceous pigment which control the activities concerned with light

• a) Phytochrome
• b) Chlorophyll
• c) Anthocyanin
• d) Carotenoids

Answer: Phytochrome

Question: 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 other set of plant?

• a) Short day
• b) Day neutral
• c) Darkness neutral
• d) Long day

Answer: Short day

Question: What will be the effect on phytochrome in a plant subjected to continuous red light?

• a) First (2) then (1)
• b) Level of phytochrome will decrease
• c) Phytochrome synthesis will increase
• d) Phytochrome will be destroyed

Answer: First (2) then (1)

Question: The pigment, that absorbs red and far red light in plants, is

• a) Phytochrome
• b) Carotene
• c) Xanthophyll
• d) Cytochrome

Answer: Phytochrome

Question: Phytochrome becomes active in

• a) Red light
• b) Green light
• c) None of these
• d) Blue light

Answer: Red light