gymnosperm


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gym·no·sperm

 (jĭm′nə-spûrm′)
n.
A vascular plant, such as a cycad or conifer, whose seeds are not enclosed within an ovary.

[From New Latin Gymnospermae, former class name, from Greek gumnospermos : gumnos, naked; see nogw- in Indo-European roots + sperma, seed; see sperm1.]

gym′no·sper′mous adj.
gym′no·sper′my n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

gymnosperm

(ˈdʒɪmnəʊˌspɜːm; ˈɡɪm-)
n
(Botany) any seed-bearing plant in which the ovules are borne naked on the surface of the megasporophylls, which are often arranged in cones. Gymnosperms, which include conifers and cycads, are traditionally classified in the division Gymnospermae but in modern classifications are split into separate phyla. Compare angiosperm
ˌgymnoˈspermous adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

gym•no•sperm

(ˈdʒɪm nəˌspɜrm)

n.
any nonflowering plant having seeds that are not enclosed in fruit at the time of pollination; any conifer, cycad, or ginkgo.
[1820–30; < New Latin gymnospermae (pl.)]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

gym·no·sperm

(jĭm′nə-spûrm′)
Any of a group of plants that produce seeds that are not enclosed in a fruit or ovary. Most gymnosperms are cone-bearing trees or shrubs. Seeds develop next to the inside surface of the scales of female cones. Gymnosperms include the conifers, the cycads, and the ginkgo. Compare angiosperm.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.gymnosperm - plants of the class Gymnospermae having seeds not enclosed in an ovarygymnosperm - plants of the class Gymnospermae having seeds not enclosed in an ovary
phanerogam, seed plant, spermatophyte - plant that reproduces by means of seeds not spores
class Gymnospermae, division Gymnospermophyta, Gymnospermae, Gymnospermophyta - plants having naked seeds not enclosed in an ovary; in some systems considered a class (Gymnospermae) and in others a division (Gymnospermophyta); comprises three subdivisions (or classes): Cycadophytina (class Cycadopsida) and Gnetophytina (class Gnetopsida) and Coniferophytina (class Coniferopsida); in some classifications the Coniferophytina are divided into three groups: Pinophytina (class Pinopsida) and Ginkgophytina (class Ginkgopsida) and Taxophytina (class Taxopsida)
progymnosperm - an ancestral fossil type from which modern gymnosperms are thought to have derived
welwitschia, Welwitschia mirabilis - curious plant of arid regions of southwestern Africa having a yard-high and yard-wide trunk like a turnip with a deep taproot and two large persistent woody straplike leaves growing from the base; living relic of a flora long disappeared; some may be 700-5000 years old
cycad - any tropical gymnosperm of the order Cycadales; having unbranched stems with a crown of fernlike leaves
pteridosperm, seed fern - an extinct seed-producing fernlike plant of the order Cycadofilicales (or group Pteridospermae)
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Although all gymnosperm pollination was thought to be anemophilous (i.e., wind pollinated), pollination of cycads by insects (entomophily) has been reported widely (Stevenson et al., 1998) and proven experimentally in seven out of 10 extant genera: Bowenia, Cycas, Encephalartos Lepidozamia, Macrozamia, Stangeria and Zamia (Xaba, 2014).
In addition, two alternative evolutionary scenarios, that is, monophyly or paraphyly of the gymnosperm YABBY family towards angiosperm YABBY genes, suggest that all spermatophyte YABBY genes were derived from one or two, respectively, YABBY genes of the last common ancestor of extant seed plants [20, 23, 29].
Antibacterial activity of Cycas circinalis ovules-a naked seeded gymnosperm. Int J Herbal Med.
This phase, at the transition of Griesbachian and Dienerian, is a time of major change with continuous decrease in Gymnosperm abundance while the lycopod abundance increases.
Several molecular mechanisms of MADS-box gene diversification were used to a quite different extent during angiosperm and gymnosperm evolution (Theiben et al., 1996; Shindo et al., 1999;Gramzow et al., 2014).
leyboldii is a gymnosperm with many angiosperm-like morphological traits, the analysis of its light acclimation and biomass allocation strategies at the seedling stage is crucial to understand the diversity of the early regeneration niche of lianas (and tropical plants in general) within the context of the light-limited forest understory.
Specifically, the rural livestock landscape from the Barbas River (Filandia-Quindio) is composed of two big native forest fragments; the forest from the Barbas River Canyon that covers about 790 ha and the Bremen Forest Reserve that has 336 ha of native forest and 447 ha of remaining gymnosperm forest plantations (Fig.
In general, the anatomical structure of gymnosperm wood is considered simple when compared with angiosperms because it is mainly composed of tracheids, interspersed by radial rays (medullar rays), and some parenchyma cells associated with resin ducts [1](Figure 2).
It is the only native gymnosperm in the region, and like all Cycas species exhibits primitive features reminiscent of early spermatophytes.
"Gymnosperms of the United States & Canada" is an illustrated guide to classification and identification of the Gymnosperm, or the naked seed of the trees of the United States and Canada.