pollen is a generative means of propagation of flowering plants carried by the wind or species that perch on the flower.
pollen can not last long in the wild.
pollen itself is not a male gamete, but each contains a pollen of vegetative (non-reproductive) cells (only one cell in most flowering plants but several other plants) and generative (reproductive) cells that contain two nuclei: a core tube ( which produces pollen tubes) and generative nuclei (which divide to form two sperm cells). A group of cells surrounded by cellulose-rich cell walls is called the intine, and the outer wall resistance consists mostly of sporopollenin called exine.
pollen is produced in microsporangium (which is contained in the anthera flowers Angiosperms, male cones from coniferous plants, or male cones of other plants). pollen comes in a variety of shapes (most often spherical), size, and surface characteristics characteristic of species (see electron micrograph in the top right). Pine pollen, fir, and winged fir. The smallest pollen grains, Myosotis spp., Are about 6 m (0.006 mm) in diameter. Wind-pollen can be as large as 90-100 μm. Pollen studies are called Palinology and are very useful in Paleoecology, paleontology, archeology, and forensics.
In angiosperms, during development anther flowers consist of cell masses that appear indistinguishable, except for partially differentiated dermis. When flowers develop, four groups of sporogenic cells form in anther, fertile sporogenous cells surrounded by sterile cell layers that grow into pollen sac walls, some cells grow into nutritional cells that provide nutrients for microspores formed by the meiotic division of sporogen cells. The four haploid microspores produced from each sporogenous diploid cell are called microsporocytes, after meiotic division. After the formation of the fourth microspora, which is contained by the kalose wall, the construction of the pollen grain wall begins. Exine is what is stored in the fossil record.
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Pollen : https://brainly.com/question/5918905
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Class : high school
Subject : biology
Keywords : Pollen, microsporangium , produced, vegetative, modification
