Description Bee pollinating a sunflower. Pollen is transferred from anther of one plant to stigma of another as bee collects nectar Pollen tubes are unique to plants and their structures have evolved over the history of seed plants . Pollen tube formation is complex and the mechanism is not fully understood, but is of great interest to scientists . Pollen tube formation is important for sexual reproduction to occur in seed plants. Wind, water or pollinators transport pollen grains to the female gametophyte. Once a pollen grain has implanted on a compatible stigma via self-incompatibility mechanisms, the germination process is initiated. During this process, the pollen grain undergoes a conformational change whereupon a given section begins to protrude outwards to form a tube-like structure, known as the pollen tube. This structure rapidly descends down the length of the style via tip-directed growth, reaching rates of 1 cm/h, whilst carrying two non-motile sperm cells. Upon reaching the ovule the pollen tube ruptures, thereby delivering the sperm cells to the female gametophyte, ultimately resulting in a double fertilization event. The first fertilization event produces a diploid zygote and the second fertilization event produces a triploid endosperm.
Description Bee pollinating a sunflower. Pollen is transferred from anther of one plant to stigma of another as bee collects nectar Pollen tubes are unique to plants and their structures have evolved over the history of seed plants . Pollen tube formation is complex and the mechanism is not fully understood, but is of great interest to scientists because pollen tubes transport the male gametes produced by pollen grains to the female gametophyte. Once a pollen grain has implanted on a compatible stigma , its germination is initiated. During this process, the pollen grain begins to bulge outwards to form a tube-like structure, known as the pollen tube. The pollen tube structure rapidly descends down the length of the style via tip-directed growth, reaching rates of 1 cm/h, whilst carrying two non-motile sperm cells. Upon reaching the ovule the pollen tube ruptures, thereby delivering the sperm cells to the female gametophyte, ultimately resulting in a double fertilization event. The first fertilization event produces a diploid zygote and the second fertilization event produces a triploid endosperm.
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. Pollen tube formation is important for sexual reproduction to occur in seed plants. Wind, water or pollinators transport
because pollen tubes transport the male gametes produced by
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via self-incompatibility mechanisms, the germination process
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undergoes a conformational change whereupon a given section begins to protrude
begins to bulge
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The pollen tube