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pollen
(Encyclopedia)pollen, minute grains, usually yellow in color but occasionally white, brown, red, or purple, borne in the anther sac at the tip of the slender filament of the stamen of a flowering plant or in the ma...anther
(Encyclopedia)anther, pollen-bearing structure of the stamen of a flower, usually borne on a slender stalk called the filament. Each anther generally consists of two pollen sacs, which open when the pollen is matur...pollination
(Encyclopedia)pollination, transfer of pollen from the male reproductive organ (stamen or staminate cone) to the female reproductive organ (pistil or pistillate cone) of the same or of another flower or cone. Polli...Frankland, William
(Encyclopedia)Frankland, William (Alfred William Frankland), 1912–2020, British allergist and immunologist. He studied medicine at Queens College, Oxford, and St. Mary's Hospital Medical School (now part of Imper...cone, in botany
(Encyclopedia)cone or strobilus strŏbˈələs [key], in botany, reproductive organ of the gymnosperms (the conifers, cycads, and ginkgoes). Like the flower in the angiosperms (flowering plants), the cone is actual...sperm
(Encyclopedia)sperm or spermatozoon spûrˌmətəzōˈən, –zōˈŏn [key], in biology, the male gamete (sex cell), corresponding to the female ovum in organisms that reproduce sexually. In higher animals the spe...hay fever
(Encyclopedia)hay fever, seasonal allergy causing inflammation of the mucous membranes of the nose and eyes. It is characterized by itching about the eyes and nose, sneezing, a profuse watery nasal discharge, and t...stamen
(Encyclopedia)stamen, one of the four basic parts of a flower. The stamen (microsporophyll), is often called the flower's male reproductive organ. It is typically located between the central pistil and the surround...ragweed
(Encyclopedia)ragweed, any plant of the genus Ambrosia, coarse, weedy herbs belonging to the family Asteraceae (aster family), most of which are native to America. They have inconspicuous greenish flowers and soft ...varve
(Encyclopedia)varve, in geology, pair of thin sedimentary layers formed annually by seasonal climatic changes. Usually found in glacial lake deposits, varves consist of a coarse-grained, light-colored summer deposi...Browse by Subject
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