Filiform apparatus is characteristic feature of
aleurone cell
synergids
generative cell
nucellar embryo.
Dichogamy which helps in cross pollination is a floral mechanism in which
Adventive polyembryony is common in
$A$ : Certain proteins of pollen origin identifies the compatible stigma.
$R$ : Compatibility proteins are found located in ektexine.
Vegetative propagation in Pistia occurs by
The gynoecium consists of many free pistils in flowers of