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Pollen itself is not the male gamete. [4] It is a gametophyte, something that could be considered an entire organism, which then produces the male gamete.Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive) cell.
Earlier pollen researchers include Früh (1885), [16] who enumerated many common tree pollen types, and a considerable number of spores and herb pollen grains. There is a study of pollen samples taken from sediments of Swedish lakes by Trybom (1888); [ 17 ] pine and spruce pollen was found in such profusion that he considered them to be ...
Pollination by water, hydrophily, uses water to transport pollen, sometimes as whole anthers; these can travel across the surface of the water to carry dry pollen from one flower to another. [41] In Vallisneria spiralis , an unopened male flower floats to the surface of the water, and, upon reaching the surface, opens up and the fertile anthers ...
A pollinium (pl.: pollinia) is a coherent mass of pollen grains in a plant that are the product of only one anther, but are transferred, during pollination, as a single unit. [1] [2] This is regularly seen in plants such as orchids and many species of milkweeds (Asclepiadoideae). Usage of the term differs: in some orchids two masses of pollen ...
In the winter, pollen levels indoors actually exceed outdoor levels. [13] Up to date data on pollen levels is critical for humans that have allergies. A current limitation is that many spore traps require scientists to identify and count individual pollen grains under magnification. [10] This causes data to be delayed, sometimes by over a week.
The distribution of these pollen grains can offer insight into the historical distribution of vegetation around the lake. [ 18 ] [ 17 ] Pollen records derived from paleolimnological assessments also allow researchers to track the distribution and density of different vegetation classes across large periods of time, and allow modeling of the ...
Pollen morphology, particularly in the Poaceae family, is key to figuring out their evolutionary relationships and how environments have changed over time. [46] Grass pollen grains, however, often look the same, making it hard to use them for detailed climate or environmental reconstructions.
A honeybee collecting pollen from a flower A pollen wasp (Jugurtia dispar), a type of wasp that exclusively feeds its larvae pollen. This is an example of a palynivore that is only a palynivore for part of its life span, as the adults of the species do not consume pollen