PGR MCQ: Plant Growth Regulators (Phytohormones)

PGR MCQ: Plant Growth Regulators or Plant Growth Hormones

Read objective questions on PGR (Plant Growth Regulators) or phytohormones. Topics: Auxin, gibberllin, cytokinin, ABA, ethylene, brassinosteroids.

TypeOnline Mock Test
Test number01
Number of questions25

Also read: Plant Physiology MCQ (Multiple Choice Questions)

Plant Growth Regulators MCQ

Question 01. Which one is a naturally occurring inhibitor?

(a). Phenols.
(b). Flavonols.
(c). Abscisic acid.
(d). All of the above.

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Question 02. Which one is a naturally occurring plant growth hormone?

(a). Gibberllin.
(b). Cytokinin.
(c). Both a and b.
(d). None of the above.

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Question 03. What is the source of brassinosteroids?

(a). Brassica napus.
(b). Brassica rapa.
(c). Brassica juncea.
(d). Brassica tournefortii.

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Question 04. What is the physiological effect of brassinosteroids at the cell level?

(a). Stimulation of elongation and fission.
(b). Activation of protein and nucleic acid synthesis.
(c). Enhancement of the photosynthetic capacity and the translocation of products.
(d). All of the above.

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Question 05. What is the physiological effect of brassinosteroids on the whole plant level?

(a). Increased resistance to unfavourable environmental factors such as stress and plant diseases.
(b). Effect on the nutritive components as well as fruit quality improvement.
(c). Shortening vegetative growth period.
(d). All of the above.

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Also read: Physiological Disorders of Flower Plants

Auxin MCQ

Question 06. To which PGR is the Avena Curvature Test associated?

(a). Ethylene.
(b). Abscisic acid.
(c). Auxin.
(d). Cytokinin.

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Question 07. Which auxin compund is known as the broad-leaves herbicide?

(a). Indole Acetic Acid.
(b). Indole Butyric Acid.
(c). Naphthalene Acetic Acid.
(d). 2, 4-D.

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Question 08. What is the primary physiological effect of auxin?

(a). Cell elongation.
(b). Apical dominance.
(c). Both a and b.
(d). None of the above.

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Question 09. Consider about the following points:

  1. Apical dominance promotes the growth of terminal as well as lateral shoots.
  2. Skoog and Thimann, in 1934, first found that the apical dominance might be under the control of auxin.
  3. The higher concentration of auxin promotes the elongation of root.
  4. The higher concentration of auxin initiates the more lateral branch roots.

(a). Only 2 and 4 are true.
(b). Only 1 and 3 are true.
(c). Only 3 and 4 are true.
(d). None of the above.

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Question 10. When you do air layering in litchi and left it for a very long period, what can be the final result?

(a). Formation of root.
(b). Formation of callus.
(c). Formation of buds.
(d). Formation of bark.

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Also read: Vegetable crops physiological disorder MCQ

Quiz on Gibberllin

Question 11. Which phytohormone is used to break the dormancy of seeds?

(a). Auxin.
(b). Gibberllin.
(c). Cytokinin.
(d). Naphthalene Acetic Acid.

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Question 12. What is the most pronounced effect of gibberllin in plant growth?

(a). Seed germination.
(b). Dormancy of buds.
(c). Elongation of the internodes.
(d). Growth of root.

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Question 13. How can you overcome the genetic dwarfism?

(a). By using auxin.
(b). By using gibberllin.
(c). Cytokinin.
(d). Any of the above.

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Question 14. How can you achieve parthenocarpy?

(a). By using auxin.
(b). By using gibberllin.
(c). Both a and b.
(d). None of the above.

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Question 15. Site of biosynthesis of gibberllin.

(a). Developing seeds and fruits.
(b). Young leaves of developing apical buds and elongating shoots.
(c). The apical regions of roots.
(d). All of the above.

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Also read: Fruit Crops Physiological Disorders MCQ

Cytokinin objective questions

Question 16. What is the specific effect of kinetin?

(a). Cell division.
(b). Cell elongation.
(c). Cell development.
(d). All of the above.

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Question 17. What is the source of zeatin?

(a). Immature corn.
(b). Mature corn.
(c). Both a and b.
(d). None of the above.

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Question 18. Which is not a cytokinin?

(a). di-hydrozeatin.
(b). N6-(∆2 – isopentenyl).
(c). ip.
(d). Guanine.

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Question 19. Which is a synthetic cytokinin?

(a). Benzyl adenine.
(b). Thidiazuron.
(c). Both a and b.
(d). Adenine.

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Question 20. What is the Richmond-Lang Effect?

(a). Delay in senescence.
(b). No senescence.
(c). Early senescence.
(d). None of the above.

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Also read: Potato Physiological Disorders

Online Mock Test on ABA and ethylene

Question 21. Who isolated ABA?

(a). Skoog.
(b). Cornforth.
(c). Addicott.
(d). Warning.

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Question 22. What are the functions of ABA?

(a). Stomatal regulations.
(b). Leaf abscission.
(c). Seed and bud dormancy.
(d). All of the above.

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Question 23. What is the tripple response?

(a). Inhibition of stem elongation.
(b). Stimulation of radial swelling of stems.
(c). Horizontal growth of stems with respect to gravity.
(d). All of the above.

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Question 24. To which plant hormone is tripple response related?

(a). ABA.
(b). Ethylene.
(c). Maleic hydrazide.
(d). None of the above.

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Question 25. What is PCD?

(a). Programmed Call Death.
(b). Programme Cell Death.
(c). Pre Call Death.
(d). Pre Cell Death.

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PGR MCQ: Plant Growth Regulators or Plant Growth Hormones

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