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
A.
It helps in the entry of pollen tube into a synergid
In most cases, the mature embryo sac contains 7-cells and nuclei. The cells are arranged egg apparatus (two synergid cell and one egg cell,) a central cell with two nuclei and antipodal cells ( 3 in number). The synergid cells occur laterally to the egg cell. These cells are characterised by finger- like projections called filiform apparatus towards the micropylar end. Fill form apparatus is formed due to invaginations of cell wall into the protoplasm and is made up of pectocellulosic fibres evolved in the non-cellulosic sheath. Secretion of chemotactic substances for the attraction of pollen tube during fertilisation is the function of synergies. One synergid becomes degenerate during pollen entry into the embryo sac and thus, provides a way for the entry of pollen tube into the embryo sac.
Male gametes in angiosperms are formed by the division of
microspore
generative cell
vegetative cell
vegetative cell
Unisexuality of flowers prevents
autogamy, but not geitonogamy
Both geitonogamy and xenogamy
geitonogamy, but not xenogamy
geitonogamy, but not xenogamy
Importance of day length in flowering of plants was first shown in
Lemna
tobacco
Cotton
Cotton
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
