The gymnosperms and angiosperms together comprise the spermatophytes or seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. They have a dominant diploid sporophyte phase and a reduced haploid gametophyte phase which is dependent on the sporophytic phase. Gymnosperm lifecycles involve alternation of generations. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, Torreya, Ginkgo. The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants ( angiosperms), which are enclosed within an ovary. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The term gymnosperm comes from the composite word in Greek: γυμνόσπερμος ( γυμνός, gymnos, 'naked' and σπέρμα, sperma, 'seed'), literally meaning 'naked seeds'. revealed seeds) are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. medicinal, harmful, edible, etc.).The gymnosperms ( / ˈ dʒ ɪ m n ə s p ə r m z, - n oʊ-/ JIM-nə-spərmz, -noh- pronunciation i lit.
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