Removal of top fertile soil by wind or water is :
Siltation
Soil erosion
Weathering of soil
Leaching
Pollination occuring from one flower to another of same plant is :
autogamy
allogamy
geitenogamy
none of these
Phytochrome occurs in two forms. In which form it promotes the germination of seeds of some species ?
Pfr forms
Pr forms
Both forms
None of these
Diadelphous stamens are the characteristic features of :
Ranunculaceae
Fabaceae
Poaceae
Malvaceae
The formation of embryo without fusion of gametes is termed as :
apospory
isogamy
apogamy
syngamy
Elater mechanism for seed dispersal is exhibited by
Riccia
Dryopteris
Funaria
Marchantia
D.
Marchantia
Marchantia is a liverwort. Its sporophyte contains elongated cells with spiral thickenings on its wall called elaters. These elaters are hygroscopic in nature. The resulting twisting movement helps dispersal of spores.