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Article: Gymnosperms
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- Biology
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CopyrightCOPYRIGHT 2002 The Gale Group Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Gymnosperms
Gymnosperms are a group of plants that share one common characteristic: they bear seeds, but their seeds do not develop within an ovary. For this reason, gymnosperms were long thought to be an evolutionary precursor to the angiosperms, which are seed plants that enclose their seeds in an ovary and that are vastly more diverse than gymnosperms. Studies of their deoxyribonucleic
acid (DNA) has shown that the gymnosperms consist of four major, related groups: conifers, cycads, ginkgo, and gnetophytes.
Conifers
With approximately 588 living species, this is the most diverse and by far the most ecologically and economically important gymnosperm group. Conifers grow in all ...