Complete the series.
implantation-uterus,Fertilization-..........

Double fertilization is

Complete the series. Secretory phase-progesterone,........ Oestrogen

In flowering plants, fertilization occur in

During sexual reproduction fertilization is an important process.But in most aquatic organisms like fishes,amphibians etc.external fertilization occur.In most terrestrial organisms internal fertilization is common. Point out the differences between external and internal fertilization.

External water is not required for fertilization of