Avena curvature test is a bioassay for examining the activity of
auxins
cytokinins
gibberellins
ethylene.
Gibberellins can promote seed germination because of their influence on
rate of cell division
production of hydrolyzing enzymes
synthesis of abscisic acid
absorption of water through hard seed coat
Pruning of plants promotes branching because the axillary buds get sensitized to
ethylene
gibberellin
cytokinin
indole acetic acid.
D.
indole acetic acid.
“It has been known since the 1930s that the plant hormone auxin is released by the plant’s actively growing tip and is transported down the main stem where it has an indirect effect on buds to inhibit branching. There are a number of ways in which the hormone exerts this effect and we have discovered a new path by which it works.”
The research suggests that for a shoot tip to be active, it must be able to export auxin into the main stem. But if substantial amounts of auxin already exist in the main stem, export from an additional shoot tip cannot be established
In a plant organ which is covered by periderm and in which the stomata are absent, some gaseous exchange still takes place through
aerenchyma
trichornes
pneumatophores
lenticels.
Cork cambium results in the formation of cork which becomes impermeable to water due to the accumulation of
resins
lignins
suberin
tannins.
'Climacteric' is
a phenomenon related to fruit ripening
the condition of a plant when all its fruits are almost ripe
the condition of a plant when most of its leaves have turned yellow
none of the above
The plants respond to photoperiods due to the presence of :
enzymes
stomata
phytochromes
phytohormones
Tendrils exhibit/twining of tendrils is due to
thigmotropism
seismonasty
heliotropism
diageotropism