Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R):
| Assertion (A): | Plants retain the capacity for unlimited growth throughout their life. |
| Reason (R): | Plants have meristems at certain locations in their body. |
In the light of the above statements choose the correct answer from the options given below:
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
To promote stem elongation, gibberellins act in concert with:
| 1. | Auxins | 2. | Cytokinins |
| 3. | Ethylene | 4. | ABA |
The removal or inactivation of which of the following will lead to germination of many types of dormant seeds?
| 1. | ABA | 2. | Ethylene |
| 3. | Cytokinins | 4. | Gibberellins |
Flowering will take place in a short day plant only when:
1. days are shorter than nights.
2. days are shorter than a certain critical value.
3. nights are shorter than a certain critical value.
4. nights are longer than a certain critical value.
Match the following :
| A. | IAA | i. | Herring sperm DNA |
| B. | ABA | ii. | Bolting |
| C. | Ethylene | iii. | Stomatal closure |
| D. | GA | iv. | Weed-free lawns |
| E. | Cytokinins | v. | Ripening of fruits |
Options:
| A | B | C | D | E | |
| 1. | iv | iii | v | ii | i |
| 2. | v | iii | iv | ii | i |
| 3. | iv | i | v | iii | ii |
| 4. | v | iii | ii | i | iv |
The site of perception of light/dark duration in plants is:
1. Root apex
2. Shoot apex
3. Flower
4. Leaves
In most situations, which PGR acts as an antagonist to GAs?
| 1. | ABA | 2. | Ethylene |
| 3. | Cytokinin | 4. | Giberrellin |
Which PGR stimulates the closure of stomata in the epidermis and increases the tolerance of plants to various kinds of stress?
| 1. | Cytokinin | 2. | Giberrellin |
| 3. | ABA | 4. | Ethylene |
Normally, when the seeds are mature, ethylene production increases and builds-up within the fruit, resulting in a climactic event that means:
| 1. | A sudden spurt of growth | 2. | Leaf expansion |
| 3. | Rise in respiratory rate | 4. | Death of radicle |
Cytokinins do not help in:
| 1. | Production of new leaves |
| 2. | Lateral shoot growth |
| 3. | Adventitious shoot formation |
| 4. | Promotion of apical dominance |