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The gymnosperms (/ ˈ dʒ ɪ m n ə ˌ s p ɜːr m z,-n oʊ-/ ⓘ nə-spurmz, -noh-; lit. ' revealed seeds ') are a group of woody, perennial seed-producing plants, typically lacking the protective outer covering which surrounds the seeds in flowering plants, that include conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae [2] The term gymnosperm comes from the ...
Angiosperms, the flowering plants, possess seeds enclosed in a fruit, unlike gymnosperms. In addition to the five living taxa listed above, the fossil record contains evidence of many extinct taxa of seed plants, among those:
Angiosperms are distinguished from the other major seed plant clade, the gymnosperms, by having flowers, xylem consisting of vessel elements instead of tracheids, endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the ...
An edible seed [n 1] is a seed that is suitable for human or animal consumption. Of the six major plant parts, [n 2] seeds are the dominant source of human calories and protein. [1] A wide variety of plant species provide edible seeds; most are angiosperms, while a few are gymnosperms.
While the form of early trees was similar to that of today's, the Spermatophytes or seed plants, the group that contain all modern trees, had yet to evolve. The dominant tree groups today are all seed plants, the gymnosperms, which include the coniferous trees, and the angiosperms, which contain all fruiting and flowering trees.
The terms angiosperms and gymnosperm fundamentally changed meaning in 1827, when Robert Brown determined the existence of truly-naked ovules in the Cycadeae and Coniferae. [3] The term gymnosperm was, from then-on, applied to seed plants with naked ovules, and the term angiosperm to seed plants with enclosed ovules. However, for many years ...
The gymnosperms consist of five orders of seed plants: Cupressales, Cycadales, Ginkgoales, Gnetales and Pinales. [a] They developed more than 350 million years ago, long before flowering plants, according to the fossil record. The name comes from the Greek for "naked seed"; the egg cells are not protected by ovaries, as in flowering plants. [4]
Gnetophyta (/ n ɛ ˈ t ɒ f ɪ t ə, ˈ n ɛ t oʊ f aɪ t ə /) is a division of plants (alternatively considered the subclass Gnetidae or order Gnetales), grouped within the gymnosperms (which also includes conifers, cycads, and ginkgos), that consists of some 70 species across the three relict genera: Gnetum (family Gnetaceae), Welwitschia (family Welwitschiaceae), and Ephedra (family ...