Which plant hormone is primarily responsible for apical dominance? MCQ with Answer and Explanation

Which plant hormone is primarily responsible for apical dominance?
A. Auxin
B. Cytokinin
C. Ethylene
D. Gibberellin
Answer: Option A
Solution (By JKSSB Mock Tests)
Auxin (indole-3-acetic acid) produced at the shoot apex suppresses the growth of lateral buds, a phenomenon called apical dominance. Removing the apex allows lateral buds to grow. Cytokinin promotes cell division and counteracts apical dominance. Gibberellin stimulates stem elongation, and ethylene is involved in fruit ripening and senescence. The auxin-cytokinin ratio determines root and shoot differentiation in tissue culture.

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What does ICZN stand for in biological nomenclature?
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B. Indian Code of Zoological Nomenclature
C. International Code for Zoological Nomenclature
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Correct Answer: Option D


Explanation:
ICZN stands for the International Commission on Zoological Nomenclature. It is the organization that establishes and maintains the International Code of Zoological Nomenclature, which provides the universal rules for naming animals to ensure stability and universality in scientific names.

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Correct Answer: Option B


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