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Question
Explain the events upto double fertilisation after the pollen tube enters one of the synergids in an ovule of an angiosperm.
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Solution
The events which occur during double fertilization are:
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Two male gametes are released by the pollen tube into the cytoplasm of synergid.
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One of these male gametes moves towards the egg cell and fuses with the nucleus. This process is called syngamy and results in the formation of a diploid cell, zygote,which eventually forms an embryo.
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The other male gamete moves towards the polar nuclei located in the central cell and fuses with them to form a triploid primary endosperm nucleus (PEN). This process is called triple fusion.
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Since two types of fusion, syngamy and triple fusion, take place here, the phenomenon is called double fertilisation.
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