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A plant hormone promotes bolting in rosette plants and is also antagonistic to the effects of abscisic acid on alpha-amylase activity. This hormone also plays a key role in apical dominance. Which of the following hormones fits this description?
Gibberellin
Auxin
Cytokinin
Ethylene
The ratio of ABA to GA in a dormant seed is typically high. Which of the following changes during seed germination is MOST directly responsible for shifting this balance and promoting growth?
Increased ABA degradation and decreased GA degradation.
Increased GA biosynthesis and decreased ABA biosynthesis.
Transport of ABA out of the embryo and GA into the embryo.
Inactivation of ABA receptors and activation of GA receptors.
A researcher observes that the growth rate of a plant significantly increases after the application of a specific hormone. Further analysis reveals that this hormone promotes cell elongation primarily in the intercalary meristem. Which hormone is most likely responsible for this observed growth?
Auxin
Cytokinin
Ethylene
Gibberellin
Gibberellins are known to promote:
Leaf abscission
Fruit ripening
Stem elongation
Root inhibition
Which plant growth regulator is applied to sugarcane crops to stimulate stem elongation and enhance sugar yield?
Auxins
Gibberellins
Cytokinins
Abscisic acid
Spraying a sugarcane field with which hormone would result in increased internode elongation and thus increased sugar production?
Ethylene
Gibberellins
Auxins
Cytokinins
Gibberellic acid is known to promote stem elongation in sugarcane, leading to increased sugar production. Which of the following best describes the primary effect of gibberellins on plant cells in this context?
Increased cell division
Increased cell differentiation
Increased cell elongation
Decreased cell senescence
Which phytohormone accelerates the maturity of juvenile conifers, leading to early seed production when sprayed?
Auxins
Gibberellins
Cytokinins
Ethylene
Juvenile conifers can be induced to produce seeds earlier than usual by applying which plant hormone?
Abscisic acid
Ethylene
Gibberellins
Cytokinins
Which of the following phytohormones is used to shorten the time to seed production in young conifer trees?
Auxins
Cytokinins
Gibberellins
Abscisic Acid