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How does pollen reach the egg nucleus in a flowering plant?
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Reproduction
Fungi produce billions of spores that give rise to new generations of fungi.
In flowering plants, the process by which pollen reaches the egg nucleus is a multi-step journey that begins with pollination.
- Deposition: Pollen grains are transferred from the stamen to the stigma, the receptive surface of the pistil, by external agents such as wind, water, or animals.12
- Germination: Once on the stigma, the pollen grain germinates to produce a pollen tube. This tube grows downward through the style, nourished by the secretory tissues within the pistil.32
- Entry: The pollen tube continues its growth until it reaches the ovule. It enters the ovule through a small opening called the micropyle.42
- Discharge: Upon entering the ovule, the pollen tube penetrates a synergid cell and discharges two nonmotile sperm cells.32
One of these sperm cells then fuses with the egg cell to complete the process of fertilization, forming a zygote.43