Biology

Plant Growth and Hormones

695 Questions

Plant growth and hormones is a vital topic in biology that covers the physiological effects of different plant regulators like auxins, gibberellins, and cytokinins. These concepts are frequently tested in various general science sections of competitive exams. Practicing these questions helps clarify complex mechanisms like vernalisation, senescence, and tropism for test takers.

Abscisic acid effectsCytokinin functionsAuxins and tropismPlant tissue cultureSenescence in plantsNatural plant hormones

Plant Growth and Hormones Questions

Multiple choice

Which of the following is a plant hormone that inhibits growth?

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Abscisic acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Abscisic acid is a plant hormone that plays a role in inhibiting growth, promoting seed dormancy, and regulating water loss.

Multiple choice

Which of the following is a plant hormone that promotes fruit ripening?

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Ethylene
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ethylene is a plant hormone that plays a role in promoting fruit ripening, senescence, and abscission.

Multiple choice

Which of the following is a plant hormone that promotes cell division and growth?

  1. Auxin

  2. Cytokinin

  3. Gibberellin

  4. Abscisic acid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cytokinin is a plant hormone that promotes cell division and growth. It is involved in various physiological processes, including shoot and root development, leaf expansion, and fruit set.

Multiple choice

Which of the following is a type of plant hormone that promotes seed germination and root growth?

  1. Auxin

  2. Cytokinin

  3. Gibberellin

  4. Abscisic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Gibberellin is a plant hormone that promotes seed germination and root growth. It also plays a role in stem elongation and fruit development.

Multiple choice

Which of the following is a type of plant hormone that inhibits growth and promotes seed dormancy?

  1. Auxin

  2. Cytokinin

  3. Gibberellin

  4. Abscisic acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Abscisic acid is a plant hormone that inhibits growth and promotes seed dormancy. It also plays a role in water stress responses and stomatal closure.

Multiple choice

Which of the following is a type of plant hormone that promotes flowering and fruit development?

  1. Auxin

  2. Cytokinin

  3. Gibberellin

  4. Abscisic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Gibberellin is a plant hormone that promotes flowering and fruit development. It also plays a role in stem elongation and seed germination.

Multiple choice

Which of the following is a common mechanism of action for many herbicides?

  1. Inhibition of photosynthesis

  2. Disruption of cell division

  3. Interference with hormone production

  4. Blocking of nutrient uptake
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Many herbicides work by inhibiting the process of photosynthesis in plants, preventing them from producing food and energy.

Multiple choice

What is the primary role of nitrogen in plant growth?

  1. Promoting root development

  2. Enhancing fruit production

  3. Stimulating leaf growth

  4. Improving seed quality
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Nitrogen is primarily responsible for stimulating leaf growth and development in plants.

Multiple choice

What is the role of abscisic acid (ABA) in plant response to drought stress?

  1. Promotes stomatal closure

  2. Induces the expression of drought-responsive genes

  3. Inhibits root growth

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Abscisic acid (ABA) plays a crucial role in plant response to drought stress by promoting stomatal closure to reduce water loss, inducing the expression of drought-responsive genes involved in stress tolerance, and inhibiting root growth to conserve water.

Multiple choice

Which hormone is primarily responsible for seed germination?

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Abscisic Acid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Gibberellin is the primary hormone that promotes seed germination by breaking seed dormancy and stimulating the growth of the embryo.

Multiple choice

The primary function of the apical meristem in plants is:

  1. Flowering

  2. Fruit Production

  3. Root Growth

  4. Shoot Growth
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The apical meristem is responsible for the continuous growth of shoots, including the stem and leaves, by producing new cells and tissues.

Multiple choice

Which hormone is involved in the regulation of apical dominance?

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Ethylene
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Auxin is the primary hormone responsible for apical dominance, which is the inhibition of lateral shoot growth by the main stem.

Multiple choice

Which hormone is primarily responsible for fruit development?

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Ethylene
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ethylene is the primary hormone involved in fruit development, promoting ripening and softening of fruits.

Multiple choice

The process of cellular differentiation during plant development is regulated by:

  1. Transcription Factors

  2. Hormones

  3. Environmental Signals

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cellular differentiation in plants is regulated by a combination of transcription factors, hormones, and environmental signals.

Multiple choice

Which hormone is involved in the regulation of leaf senescence?

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Abscisic Acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Abscisic Acid (ABA) is the primary hormone involved in the regulation of leaf senescence, promoting the breakdown of chlorophyll and the reabsorption of nutrients from leaves.