Question
Explain the post pollination events up to double fertilisation, that occur in an angiosperm.
✓
Answer
Post pollination event up.to double fertilization, that occur in an angiosperm is as follows:
The Pollen grain germinates on the stigma to produce pollen tube through one of the germ pore, the contents of the pollen grain/vegetative cell/generative cell/two male gametes move into the pollen tube, the pollen tube grows through the tissues of stigma and pollen tube to reach the ovary, the pollen tube enters (through micropyle) enters the synergids through filiform apparatus, pollen tube releases two male gametes in the cytoplasm of the synergids, one of the male gametes fuses with egg cell/female gamete completing syngamy, to form (diploid) zygote, the other male gamete fuses with two polar nuclei in the
(central cell) to produce (triploid) primary endospermic cell, three haploid cells fuse called triple fusion, two type of fusion syngamy and triple fusion is called double fertilisation.
The Pollen grain germinates on the stigma to produce pollen tube through one of the germ pore, the contents of the pollen grain/vegetative cell/generative cell/two male gametes move into the pollen tube, the pollen tube grows through the tissues of stigma and pollen tube to reach the ovary, the pollen tube enters (through micropyle) enters the synergids through filiform apparatus, pollen tube releases two male gametes in the cytoplasm of the synergids, one of the male gametes fuses with egg cell/female gamete completing syngamy, to form (diploid) zygote, the other male gamete fuses with two polar nuclei in the
(central cell) to produce (triploid) primary endospermic cell, three haploid cells fuse called triple fusion, two type of fusion syngamy and triple fusion is called double fertilisation.
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