Question
What does an interaction between pollen grains and its compatible stigma result in after pollination? List two steps in sequence that follow after the process.
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Answer
When the pollen grains fall on the stigma, the pollen tube enters one of the synergids and releases two male gametes.
- One of the male gametes moves towards the egg cell and fuses with it to complete syngamy to form the zygote.
- The other male gamete fuses with the two polar nuclei and forms triploid Primary Endosperm Nucleus (PEN).
This is termed as triple fusion.
- Since, two kinds of fusion-syngamy and triple fusion take place, the process is known as double fertilization and is charactedstic of flowering plants.
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