Importance of day length in flowering of plants was first shown in
Lemna
tobacco
Cotton
Cotton
B.
tobacco
The phenomenon of photoperiodism was first discovered by Garner and Allard (1920, a mammoth variety of tobacco could be made to flower only by reducing the light hours with artificial darkening. On the basis of photoperiodic response to flowering, plants (tobacco), long day plant (eg, wheat, hanbane), short - long day plant (eg Campanula), long short day plants, (eg, wild kidney bean) and day neutral plants (eg, cotton).
What does the filiform apparatus do at the entrance into ovule?
It helps in the entry of pollen tube into a synergid
It prevents entry of more than one pollen tube into the embryo sac
It brings about opening of the pollen tube
It brings about opening of the pollen tube
Unisexuality of flowers prevents
autogamy, but not geitonogamy
Both geitonogamy and xenogamy
geitonogamy, but not xenogamy
geitonogamy, but not xenogamy
Which one of the flowing pairs of plants structures has haploid number of chromosomes?
Megaspore mother cell and antipodal cells
Egg cell and antipodal cells
Nucellus and antipodal cells
Nucellus and antipodal cells
Male gametes in angiosperms are formed by the division of
microspore
generative cell
vegetative cell
vegetative cell
