One of the first gibberellins to be discovered and also the one that remains the most intensively studied form is:
1. GA1
2. GA2
3. GA3
4. GA4

Subtopic:  Gibberellin |
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Consider the two statements:
Assertion (A): Gibberellins are used to increase the length of grape stalks.
Reason (R): Gibberellins help overcome apical dominance.
 
1. Both (A) and (R) are True and (R) correctly explains (A).
2. Both (A) and (R) are True but (R) does not correctly explain (A).
3. (A) is True; (R) is False.
4. (A) is False; (R) is True.
Subtopic:  Gibberellin | Cytokinin |
 81%
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Consider the two statements:
Assertion (A): GA3 is used in brewing industry.
Reason (R): GA3 speeds up the malting process.
 
1. Both (A) and (R) are True and (R) correctly explains (A).
2. Both (A) and (R) are True but (R) does not correctly explain (A).
3. (A) is True; (R) is False.
4. (A) is False; (R) is True
Subtopic:  Gibberellin |
 90%
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Consider the two statements:
Assertion(A): Spraying juvenile conifers with GAs delays seed production.
Reason(R): Spraying juvenile conifers with GAs delays the onset of maturity period.
 
1. Both (A) and (R) are True and (R) correctly explains (A).
2. Both (A) and (R) are True but (R) does not correctly explain (A).
3. (A) is True; (R) is False.
4. (A) is False; (R) is False.
Subtopic:  Gibberellin |
 73%
From NCERT
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Which plant growth regulator (PGR) promotes bolting (internode elongation just prior to flowering) in beet, cabbages and many plants with rosette habits?
1. Auxins
2. Gibberellins
3. Ethylene
4. Kinetins
Subtopic:  Gibberellin |
 94%
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Consider the given two statements:
Statement I: Kinetin, a modified form of adenine, a purine, was discovered from the autoclaved herring sperm DNA.
Statement II: Search for natural substances with cytokinin-like activities led to the isolation of zeatin from corn-kernels and coconut milk.

1. Statement I is correct; Statement II is incorrect
2. Statement I is correct; Statement II is correct
3. Statement I is incorrect; Statement II is correct
4. Statement I is incorrect; Statement II is incorrect
Subtopic:  Growth Hormones & Auxin | Cytokinin |
 93%
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All the following are physiological functions of Ethylene in plants except:
1. It breaks seed and bud dormancy
2. It delays germination in peanut seeds
3. It leads to sprouting of potato tubers
4. It promotes rapid internode/petiole elongation in deep water rice plants
Subtopic:  Ethylene |
 78%
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Which plant growth regulator (PGR) promotes root growth and root hair formation, thus helping the plants increase their absorption surface?
1. Auxins
2. Gibberellins
3. Ethylene
4. Kinetins
Subtopic:  Ethylene |
 76%
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Ethylene:
I: is used to initiate flowering and for synchronising fruit-set in pineapples.
II: induces flowering in mangoes.

1. Only I is correct
2. Only II is correct
3. Both I and II are incorrect
4. Both I and II are correct
Subtopic:  Ethylene |
 82%
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Ethephon:
I: retards fruit ripening in tomatoes and apples.
II: retards abscission in flowers and fruits in cotton, cherry, walnut.
III: promotes male flowers in cucumbers thereby decreasing the yield.

1. Only I and II are correct
2. Only III is incorrect
3. Only I is correct
4. I, II and III are incorrect
Subtopic:  Ethylene |
 81%
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