GYMNOSPERM


Meaning of GYMNOSPERM in English

n.

Any woody plant that reproduces by means of a seed (or ovule) in direct contact with the environment, as opposed to an angiosperm, or flowering plant , whose seeds are enclosed by mature ovaries, or fruits.

The four surviving gymnosperm divisions are Coniferophyta ( conifers , the most widespread), Cycadophyta ( cycads ), Ginkgophyta ( ginkgos ), and Gnetophyta. More than half are trees; most of the rest are shrubs. Gymnosperms occur on all continents except Antarctica, and especially in the temperate latitudes. Those widely found in the Northern Hemisphere are junipers , firs , larches , spruces , and pines ; in the Southern Hemisphere, podocarps ( Podocarpus ). The wood of gymnosperms is often called softwood to differentiate it from the hardwood of angiosperms. Many timber and pulp trees are also planted as ornamentals. Gymnosperms also are a minor source of food; of essential oils used in soaps, air fresheners, disinfectants, pharmaceuticals, cosmetics, and perfumes; of tannin, used for curing leather; and of turpentines . Gymnosperms were a major component in the vegetation that was compressed over millions of years into coal . Most are evergreen . They produce male and female reproductive cells in separate male and female strobili (see cone ).

Britannica Concise Encyclopedia.      Краткая энциклопедия Британика.