 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.
<clarity>  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.
 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.