Role of Abscisic Acid

Q.

What is the main function of gibberellins?

Q.

Differentiate between the following:

Plant growth promoters and inhibitors

Q.

Which is plant growth inhibitor?

Q. Seeds can become dormant because of

1. impermeable or hard seed coat
2. chemical inhibitors
3. immature embryos
4. all the above

Q.

Gibberellins can facilitate seed germination because they can influence the

1. synthesis of abscisic acid

2. rate of cell division

3. production of hydrolyzing enzymes

4. absorption of water through the hard seed coat

Q. Which one of the following is known as the stress hormone?

1. Abscisic acid
2. Ethylene
3. Gibberellins
4. All of the above

Q.

Name one application of GA3.

Q.

Name any two processes in which inhibitory plant growth regulators are involved.

Q. Which of the following is not a method of breaking dormancy of seeds?
Method 1:Hydraulic pressure can be applied on seeds for 5-20 minutes which can weaken the seed coat
Method 2: use of inhibitors can help in breaking dormancy of seeds.
Method 3:Rupturing the seed coat by filing or chipping through machineries helps in breaking dormancy of seeds.

1. Method 1 and 3
2. Only method 2
3. Only method 3
4. Method 1, 2 and 3

Q. Which of the following is/are plant growth inhibitor(s)?

1. Auxin
2. Abscisic acid
3. Cytokinin
4. Ethylene

Q.

Assertion (A): Decapitation of shoot tip in plants induces the growth of their lateral buds

Reason (R): Accumulation of auxins in lateral buds causes inhibition of their growth

1. Both A & R are true and R explains A
2. Both A & R are true and R does not explain A
3. A is true and B is false
4. Both A & B are false

Q. Which of the following is a function of abscisic acid?

1. Helps to overcome dwarfism in genetically dwarf plants.
2. Promotes flowering
3. Promotes bolting
4. Promotes closure of stomata

Q.

Which one of the following growth regulators is known as stress hormone?

1. Abscisic acid

2. Ethylene

3. $G{A}_3$

4. Indole acetic acid

Q. Which of the following options is/are correct with respect to abscisic acid?

1. It hastens the maturity period in juvenile conifers
2. It controls xylem differentiation
3. It enables the plant to withstand stressful conditions
4. All the above

Q. Identify the right pair of hormones that act as plant growth promoters from the options given below.

1. Gibberellin and cytokinin
2. Abscisic acid and auxin
3. Gibberellin and abscisic acid
4. Abscisic acid and ethylene

Q. Select the correct statements:
i. A seed may fail to germinate due to impermeable and hard seed coat.
ii. Carrot is an annual plant.
iii. The site of perception of light in plants is shoot apices.

1. Only i is correct
2. Both i and iii are correct
3. Only ii is correct
4. Both ii and iii are correct

Q. Which of the following options is/are correct with respect to abscisic acid?

1. It hastens the maturity period in juvenile conifers
2. It controls xylem differentiation
3. It enables the plant to withstand stressful conditions
4. All the above

Q.

The plant hormone produced during adverse environmental conditions is ______.

1. Ethylene

2. Kinetin

3. Dichlorophenoxy acetic acid

4. Abscisic acid

Q. Which of the following hormone is a plant growth inhibitor?

1. Auxin
2. Gibberellin
3. Abscisic acid
4. Cytokinin

Q. Which of the following is not a function of abscisic acid?

1. It helps the seeds to survive under extreme unfavourable conditions
2. It helps in the storage of seed for agricultural purpose.
3. It induces elongation of stem
4. It induces the closure of stomata

Q.

The plant hormone produced during adverse environmental conditions is ______.

1. Ethylene

2. Kinetin

3. Dichlorophenoxy acetic acid

4. Abscisic acid

Q. Given in the table are the properties of two plant growth regulators A and B. Observe the table and identify the correct plant growth regulator that corresponds to each column.

A	B
Triggers elongation of stem	Inhibits plant metabolism
Promotes bolting	Promotes closure of stomata
Mobilize food reserves in germinating seeds	Produce seed dormancy

1. A- Abscisic acid, B- Gibberellins
2. A- Gibberellins, B-Abscisic acid
3. A- Gibberellins, B- Ethylene
4. A- Ethylene, B-Abscisic acid

Q. Which of the following is/are causes of seed dormancy?

1. Impermeable and hard seed coat
2. Presence of chemical inhibitors like phenolic acid.
3. Immature embryos
4. All of the above

Q. Match the following hormones with their functions.

Hormones	Function
1.Ethylene	i. Helps in cell division.
2.Gibberellin	ii. Induces dormancy in buds and seeds
3.Cytokinin	iii. Helps in the ripening of fruit
4.Abscisic acid	iv. Causes bolting in plants

1. 1-i, 2-iv, 3-iii, 4-ii
2. 1-ii, 2-iv, 3-i, 4-iii
3. 1-iv, 2-i, 3-iii, 4-ii
4. 1-iii, 2-iv, 3-i, 4-ii

Q. Which of the following effects is due to abscisic acid?

1. Induction of dormancy in buds or seeds
2. Inhibition of growth
3. Senescence
4. All of the above