Microscopic particles released from trees, weeds, grasses, and flowers meant to fertilize parts of other plants. The lighter ones, commonly ragweed, Kentucky bluegrass, Bermuda grass, oak, ash, elm, and several others, travel easily through the air, especially on sunny, windy days. Samples of ragweed pollen have been collected 400 miles out at sea and two miles up into the atmosphere.
Pollen is the name commonly given to the dust-like material found in flowering plants and other groups of plants such as gymnosperms and cycads. It is produced by the pollen sacs of the anthers in massive quantities, and shed when these sacs burst. It is either spread by the wind or by some pollination vector such as insects or bats. Individual pollen grains are microscopically small, and so what is normally known as 'pollen' is actually a mass of pollen grains stuck together for mass transport.
The microgametophyte of seed plants, enclosed in the microspore wall. In fossil pollen, only the microspore wall, or exine, remains after lithification removes the microgametophyte and intine. Similarly, the exine is all that remains after acetolysis of modern pollen.
Pollen is the male reproductive part of trees, grasses and weeds. Pollen allergens are carried by the wind, and when inhaled can cause an allergic reaction in the lungs or nose, leading to asthma and allergy symptoms. In general, tree pollens are present in the early spring, grass pollens in the late spring, and ragweed pollens in the late summer.
Pollen is the fine powder like material that is produced by the anthers of seed plants. Pollen is comprised of the fine spores from a male flowering plant. Plants cannot produce seeds without the male and female plants each contributing genetic material. Pollen, floating on the wind or being carried from plant to plant by insects, assures the fertilization of female flowers, which will then produce seeds.
The word pollen is derived from the Latin word meaning fine flour or dust. Pollen is a collective noun that is treated as singular. A single individual is a pollen grain. A pollen grain is a microscopic plant that carries the male genome, which is one-half the genetic complement of the parent plant. The pollen grain produces the sperm that fertilizes the ovum, or female genetic complement, of the plant. The fertilized ovum develops into a seed.
the powdery particles produced by trees, grasses, flowers, and weeds that are used in reproduction. Pollen can be carried by the wind, collected on hair and clothing, and transported by shoes. Inhaling pollen often stimulates allergic reactions.
Small, light, dry protein particles from trees, grasses, flowers, and weeds that may be spread by the wind. Pollen particles are usually the male sex cells of the plant, and are smaller than the tip of a pin. Pollen is a potent stimulator of allergic responses. It lodges in the mucus membranes that line the nose and in other parts of the respiratory tract, causing irritation and histamine reactions. See the entire definition of Pollen
The plant equivalent of sperm produced in abundance by anthers, the male reproductive organs found in most flowering plants. Immature pollen grains called microspores have significant biotechnological implications.
The male element in flowering plants; usually a fine dust produced by the anthers, which, by contact with the stigma effects the fecundation of the seeds. This impregnation is brought about by means of tubes (pollen-tubes) which issue from the pollen-grains adhering to the stigma, and penetrate through the tissues until they reach the ovary. 166
Developed by the anther, the dust-like grains of pollen have a distinctive shape and elaborately sculptured outer wall. Pollen grains contain two cells, one of which forms a pollen tube with two sperm cells.
Pollen, sometimes incorrectly called flower sperm, is a fine to coarse powder consisting of microgametophytes (pollen grains), which produce the male gametes (sperm cells) of seed plants. Each pollen grain contains vegetative cells (only one in most flowering plants but several in other seed plants) and a generative cell containing a tube nucleus (that produces the pollen tube) and a generative nucleus (that divides to form the two sperm cells). The group of cells is surrounded by a cellulose cell wall and a thick, tough outer wall made of sporopollenin.