Which PGR is used to initiate flowering and for synchronizing fruit set in pineapple?
1. | Cytokinin | 2. | ABA |
3. | Ethylene | 4. | GA |
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 |
In most situations, which PGR acts as an antagonist to GAs?
1. | ABA | 2. | Ethylene |
3. | Cytokinin | 4. | Giberrellin |
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. |
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 help in delay of leaf senescence because they:
1. | Promote new leaves formation |
2. | Help overcome apical dominance |
3. | Help in chloroplast formation in leaves |
4. | Promote nutrient mobilization |
Cytokinins do not help in:
1. | Production of new leaves |
2. | Lateral shoot growth |
3. | Adventitious shoot formation |
4. | Promotion of apical dominance |
Kinetin was first discovered from:
1. | Herring sperm DNA | 2. | Coconut milk |
3. | Yeast extract | 4. | Corn kernels |
To extend their market period, fruits can be left on trees longer by the application of:
1. | Auxin | 2. | Gibberellins |
3. | Cytokinin | 4. | ABA |
Auxin was first isolated from:
1. | Coconut milk | 2. | Barley endosperm |
3. | Oat coleoptiles | 4. | Human urine |