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Answer:
Many flowers have the stalk for support, called as ‘pedicel’ and such flowers are called
as ‘pedicellate’ whereas flower without stalk is called as ‘sessile’.
Androecium is male whorl and its members are called as stamens. Gynaecium is
female whorl and its members are called as carpels.
These may be separate or united. Ovary is present at the basal end of each carpel. A
hollow ‘style’ comes up from the ovary. Stigma is present at the tip of style. Ovary contains
one or many ovules. Embryo sac is formed in each ovule by meiosis. Each embryo sac
consists of a haploid egg cell and two haploid polar nuclei.
Pollen grains from anther are transferred to the stigma. This is called as pollination.
Pollination occurs with the help of abiotic agents (wind, water) and biotic agents
(insects and other animals). Stigma becomes sticky during pollination Pollens germinate
when they fall upon such sticky stigma i.e. a long pollen tube and two male gametes are
formed. The pollen tube carries male gametes. Pollen tube reaches the embryo sac via
style. Tip of the pollen tube bursts and two male gametes are released in embryo sac.
One male gamete unites with the egg cell to form zygote. This is fertilization. Second
male gamete unites with two polar nuclei and endosperm is formed. As two male nuclei
participate in this process, it is called as double fertilization.
Make an video album of pollination and show it in the class.
Pollen grain
Synergi
1.barter 2.lending 3.cheque 4.fiduciary 5.RBI