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
Vernalisation is subjected to plants growing in ?
(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?
(3) Gibberellic acid
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
Refrigerated fruits maintain flavour and taste for longer period due to:-
(1) non-availability of O2
(2) the presence of excess of CO2
(3) the presence of excess humidity
(4) slower rate of respiration
The biological clock measures the length at each night by the?
(1) relative amount of red absorbing and far-red absorbing phytochrome present at dawn
(2) amount of far-red absorbing phytochrome at dusk
(3) relative amount of red absorbing and far-red absorbing phytochrome at mid day
(4) rate at which are kind of phytochrome is converted to the other