(paul-len) - a fine powder produced by grass, trees and weeds that causes allergic reactions and hay fever
[n] 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
Pollen is a fine powder produced by flowers. It fertilizes other flowers of the same species so that they produce seeds. a fine powder produced by flowers, which is carried by the wind or by insects to other flowers of the same type, making them produce seeds. Mass of microscopic spores in a seed plant that appears usually as a fine dust. Each pollen grain is tiny, varies in shape and structure, is formed in the stamens in seed plants, and is transported by various means (see pollination) to the pistil, where fertilization occurs. The outer layer of a pollen grain is very resistant to disintegration; treatment with intense heat, strong acids, or strong bases has little effect on it. Because the grains often are very distinctive, some plant species may be identified by their pollen grains alone. Common components of both recent and ancient geologic sediments, pollen grains have provided much information on the origin and geologic history of plant life on land. Pollen is produced in such quantities that it is a significant part of the airborne components of earth's atmosphere. The protein-containing substance in many pollen grains (e.g., ragweed and many grasses) causes the allergic reaction commonly known as hay fever
Fine, powdery, yellowish grains that are the fertilizing element of flowering plants
Pollen, essentially, contains the male gametophytes (sex cells) It is produced in the anther See also: pollination
Microscopic particles from the male flower that can fertilize the female flower to produce seed Allergenic pollen is usually from wind-pollinated plants Sinusitis - Infection in the cavities of facial bones Symptoms include pressure or pain around or below the eyes, persistent yellow nasal discharge, mucus drainage in the throat, and nasal stuffiness Urticaria - Hives A rash consisting of irregularly shaped itchy wheals that come and go within a 24 hour period Chronic urticaria is urticaria that persists for 3 or more months continuously, usually with no obvious external cause, and sometimes found to be due to an autoimmune process in the body
The pollen grains of the various species of grasses, plants, trees and flowers are quite distinctive Palynology, the study of the pollen which accompanies archæological finds, enables us to determine what plants grew in former times, and from this, we can determine something of the climatic conditions at the time Pollen is virtually indestructible A pollen diagram shows the relative proportions of the pollen of plants over a period of time, thereby giving a picture of the vegetation and the climate at the time