Plant Hormones MCQ NEET

1. Which plant hormone is responsible for cell elongation and growth?
a) Auxin
b) Gibberellin
c) Cytokinin
d) Abscisic acid

Answer: a) Auxin

2. Which plant hormone is involved in the promotion of seed germination?
a) Abscisic acid
b) Gibberellin
c) Ethylene
d) Cytokinin

Answer: b) Gibberellin

3. Which plant hormone is known as the “stress hormone” and regulates responses to environmental stress such as drought and salinity?
a) Gibberellin
b) Abscisic acid
c) Ethylene
d) Cytokinin

Answer: b) Abscisic acid

4. The senescence of leaves is regulated by which plant hormone?
a) Gibberellin
b) Auxin
c) Ethylene
d) Cytokinin

Answer: c) Ethylene

5. Which plant hormone is responsible for the promotion of lateral bud growth and inhibition of apical dominance?
a) Auxin
b) Gibberellin
c) Cytokinin
d) Ethylene

Answer: c) Cytokinin

6. Which of the following plant hormones is involved in the closing of stomata during water stress?
a) Gibberellin
b) Auxin
c) Ethylene
d) Abscisic acid

Answer: d) Abscisic acid

7. The triple response in seedlings, characterized by a thickened, shorter stem, is associated with the action of which plant hormone?
a) Gibberellin
b) Auxin
c) Ethylene
d) Cytokinin

Answer: c) Ethylene

8. Which plant hormone is responsible for phototropism and gravitropism in plant shoots?
a) Gibberellin
b) Auxin
c) Cytokinin
d) Abscisic acid

Answer: b) Auxin

9. The breaking of dormancy in seeds is primarily regulated by which plant hormone?
a) Gibberellin
b) Auxin
c) Ethylene
d) Cytokinin

Answer: a) Gibberellin

10. Which plant hormone is involved in the regulation of cell division and differentiation in plant tissues?
a) Gibberellin
b) Auxin
c) Cytokinin
d) Ethylene

Answer: c) Cytokinin

11. Which plant hormone is responsible for promoting cell elongation and cell division?
a) Abscisic Acid (ABA)
b) Gibberellins (GA)
c) Auxins
d) Cytokinins

Answer: c) Auxins

12. Which plant hormone is involved in the regulation of seed dormancy and abscission of leaves and fruits?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Ethylene
d) Cytokinins

Answer: b) Abscisic Acid (ABA)

13. The “triple response” in plants, characterized by a thickening of the stem, slowing of stem elongation, and horizontal growth, is a response to which hormone?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Ethylene
d) Auxins

Answer: c) Ethylene

14. Which plant hormone is primarily responsible for promoting root growth and inhibiting shoot growth?
a) Cytokinins
b) Gibberellins (GA)
c) Abscisic Acid (ABA)
d) Auxins

Answer: d) Auxins

15. The breaking of seed dormancy and promotion of germination are functions associated with which plant hormone?
a) Ethylene
b) Cytokinins
c) Gibberellins (GA)
d) Abscisic Acid (ABA)

Answer: c) Gibberellins (GA)

16. Which plant hormone is commonly known as the “stress hormone” and is involved in responses to environmental stresses such as drought and salinity?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Auxins
d) Ethylene

Answer: b) Abscisic Acid (ABA)

17. What is the primary function of cytokinins in plants?
a) Inhibition of root growth
b) Promotion of leaf abscission
c) Promotion of cell division
d) Inhibition of seed germination

Answer: c) Promotion of cell division

18. Which plant hormone is responsible for the opening and closing of stomata in leaves?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Auxins
d) Ethylene

Answer: b) Abscisic Acid (ABA)

19. In which plant organ is ethylene primarily produced?
a) Roots
b) Leaves
c) Flowers
d) Fruits

Answer: d) Fruits

20. What is the role of gibberellins in plant growth and development?
a) Inhibition of seed germination
b) Promotion of stem elongation
c) Promotion of leaf abscission
d) Inhibition of flowering

Answer: b) Promotion of stem elongation

21. Question: Which plant hormone is involved in the promotion of fruit ripening and senescence in plants?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Auxins
d) Ethylene

Answer: d) Ethylene

22. Question: What is the primary role of auxins in phototropism?
a) Inhibition of stem elongation
b) Promotion of root growth
c) Promotion of stem elongation on the shaded side
d) Inhibition of leaf expansion

Answer: c) Promotion of stem elongation on the shaded side

23. Question: Which plant hormone is responsible for the prevention of premature leaf senescence and promotes chlorophyll retention?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Cytokinins
d) Auxins

Answer: c) Cytokinins

24. Question: The process of apical dominance is primarily regulated by which plant hormone?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Auxins
d) Ethylene

Answer: c) Auxins

25. Question: Which plant hormone is responsible for promoting the elongation of cells in the shoot apex, leading to cell division and differentiation?
a) Gibberellins (GA)
b) Abscisic Acid (ABA)
c) Auxins
d) Ethylene

Answer: a) Gibberellins (GA)