Phytohormones are?
| 1. | hormones regulating growth from seed to adulthood |
| 2. | growth regulators synthesised by plants and influencing physiological process |
| 3. | hormones regulating flowering |
| 4. | hormones regulating secondary growth |
Refer the given figures on photoperiodism and select the correct option.
Abscisic acid is known as the stress hormone because it
| 1. | breaks seed dormancy |
| 2. | induces flowering |
| 3. | promotes leaf fall |
| 4. | promotes closure of stomata |
Which of the following plant growth regulators (PGRs) promotes root initiation, flowering and
induced parthenocarpy?
| 1. | Gibberellin | 2. | Auxin |
| 3. | Cytokinin | 4. | Ethylene |
Vernalisation is subjected to plants growing in ?
(1) tropical
(2) sub tropical areas
(3) temperate areas
(4) hot region/arctic region
Gibberellins can promote seed germination because of their influence on
| 1. | rate of cell division |
| 2. | production of hydrolyzing enzymes |
| 3. | synthesis of abscisic acid |
| 4. | absorption of water through hard seed coat |
One hormone hastens maturity period in juvenile conifers, a second hormone controls xylem differentiation, while the third hormone increases the tolerance of plants to various stresses.They are respectively:-
| 1. | Gibberellin, Auxin, Ethylene |
| 2. | Auxin, Gibberellin, Cytokinin |
| 3. | Gibberellin, Auxin, ABA |
| 4. | Auxin, Gibberellin, ABA |
Identify the incorrect statement about ABA growth regulator.
| 1. | It increases the tolerance of plants against different stresses. |
| 2. | It acts as general plant growth inhibitor and inhibitor of metabolism. |
| 3. | It helps in seed maturation and dormancy. |
| 4. | It promotes morphogenesis and differentiation of shoots. |
Which of the following plant growth hormone increase the yield of sugar by increasing the length of stem in sugarcane?
| 1. | Cytokinin | 2. | Ethylene |
| 3. | Gibberellic acid | 4. | Auxin |
In the process of apical dominance, lateral buds are unable to grow in the presence of apical bud. This is due to:-
| 1. | less amount of cytokinins in lateral buds |
| 2. | more amount of cytokinins in lateral buds |
| 3. | less amount of auxin in lateral buds |
| 4. | more amount of auxin in lateral buds |