“gymnosperm”的概念、定义、翻译、参考文献-科学参考

gymnosperm

Biology

Any plant whose ovules and the seeds into which they develop are borne unprotected, rather than enclosed in ovaries, as are those of the flowering plants (the term gymnosperm means naked seed). In traditional systems of classification such plants were classified as the Gymnospermae, a class of the Spermatophyta, but they are now divided into separate phyla: Coniferophyta (conifers), Cycadophyta (cycads), Ginkgophyta (ginkgo), and Gnetophyta (e.g. Welwitschia). See also progymnosperms.

Geology and Earth Sciences

A seed plant in which the ovules are carried naked on the cone scales, in contrast to the angiosperms, in which they are enclosed by an ovary. Gymnosperms date from the Carboniferous and subsequently dominated the floras of the world until the Cretaceous, since when they have been progressively displaced by the angiosperms (flowering plants).

单词	gymnosperm
释义	gymnosperm Biology Any plant whose ovules and the seeds into which they develop are borne unprotected, rather than enclosed in ovaries, as are those of the flowering plants (the term gymnosperm means naked seed). In traditional systems of classification such plants were classified as the Gymnospermae, a class of the Spermatophyta, but they are now divided into separate phyla: Coniferophyta (conifers), Cycadophyta (cycads), Ginkgophyta (ginkgo), and Gnetophyta (e.g. Welwitschia). See also progymnosperms. Geology and Earth Sciences A seed plant in which the ovules are carried naked on the cone scales, in contrast to the angiosperms, in which they are enclosed by an ovary. Gymnosperms date from the Carboniferous and subsequently dominated the floras of the world until the Cretaceous, since when they have been progressively displaced by the angiosperms (flowering plants).
随便看	ancestral trait anchialine anchimeric assistance anchimetamorphism anchor anchor image anchor ring anchor tenant ancien régime ancient biomolecule Ancient Cratered Terrain ancient DNA ancillary equipment ancillary statistic ANCOVA and andalusite AND circuit ANDE Andean Community Andean orogenic belt Anderson bridge Anderson, Carl David Anderson, Carl David (1905–91) Anderson, Clayton Conrad (1959– )