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The '''gymnosperms''' ({{IPAc-en|'|dʒ|ɪ|m|n|ə|ˌ|s|p|ɜːr|m|z|,_|-|n|oʊ|-|audio=en-us-gymnosperm.ogg}} {{respell|JIM|nə|spurmz|,_|-|noh|-}}; {{lit|revealed seeds}}) are a group of [[spermatophyte|seed-producing plants]] that includes [[Pinophyta|conifers]], [[cycad]]s, ''[[Ginkgo]]'', and [[gnetophyta|gnetophyte]]s, forming the clade '''Gymnospermae'''. The term ''gymnosperm'' comes from the composite word in {{lang-el|γυμνόσπερμος}} ({{lang-el|γυμνός|translit=gymnos|lit=naked|label=none}} and {{lang-el|σπέρμα|translit=sperma|lit=seed|label=none}}), literally meaning 'naked seeds'. The name is based on the unenclosed condition of their seeds (called [[ovule]]s in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants ([[angiosperms]]), which are enclosed within an [[Ovary (botany)|ovary]]. Gymnosperm seeds develop either on the surface of scales or [[Leaf|leaves]], which are often modified to form [[Conifer cone|cones]], or on their own as in [[Taxus|yew]], ''[[Torreya]]'', ''[[Ginkgo]]''.<ref name="TPL">{{cite web|url=http://www.theplantlist.org/browse/G/|title=Gymnosperms on The Plant List|publisher=Theplantlist.org|access-date=2013-07-24|archive-date=2013-08-24|archive-url=https://web.archive.org/web/20130824024109/http://www.theplantlist.org/browse/G/|url-status=dead}}</ref>
The gymnosperms and [[angiosperms]] together constitute the [[spermatophyte]]s or seed plants. The spermatophytes are subdivided into five [[Division (botany)|divisions]], the angiosperms and four divisions of gymnosperms: the [[Cycadophyta]], [[Ginkgophyta]], [[Gnetophyta]], and [[Pinophyta]] (also known as Coniferophyta). Newer classification place the gnetophytes among the conifers.<ref>{{Cite journal |last1=Yang |first1=Yong |last2=Ferguson |first2=David Kay |last3=Liu |first3=Bing |last4=Mao |first4=Kang-Shan |last5=Gao |first5=Lian-Ming |last6=Zhang |first6=Shou-Zhou |last7=Wan |first7=Tao |last8=Rushforth |first8=Keith |last9=Zhang |first9=Zhi-Xiang |date=2022-07-01 |title=Recent advances on phylogenomics of gymnosperms and a new classification |journal=Plant Diversity |language=en |volume=44 |issue=4 |pages=340–350 |doi=10.1016/j.pld.2022.05.003 |issn=2468-2659 |pmc=9363647 |pmid=35967253|bibcode=2022PlDiv..44..340Y }}</ref> Numerous extinct seed plant groups are recognised including those considered [[Pteridospermatophyta|pteridosperms/seed ferns]], as well other groups like the Bennettitales.<ref name="Raven-2013">{{Cite book|title=Biology of Plants|last=Raven|first=P.H.|publisher=New York: W.H. Freeman and Co.|year=2013}}</ref>
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During pollination, pollen grains are physically transferred between plants from the pollen cone to the ovule. Pollen is usually moved by wind or insects. Whole grains enter each ovule through a microscopic gap in the ovule coat ([[integument]]) called the micropyle. The pollen grains mature further inside the ovule and produce sperm cells. Two main modes of fertilization are found in gymnosperms. Cycads and ''[[Ginkgo]]'' have [[flagellum|flagellated]] motile sperm<ref name="AJB">{{cite journal |last1=Southworth |first1=Darlene |last2=Cresti |first2=Mauro |title=Comparison of flagellated and nonflagellated sperm in plants |journal=American Journal of Botany |pages=1301–1311 |doi=10.2307/2446056 |date=September 1997|volume=84 |issue=9 |jstor=2446056 |pmid=21708687 |doi-access=free }}</ref> that swim directly to the egg inside the ovule, whereas conifers and [[gnetophyte]]s have sperm with no flagella that are moved along a [[pollen tube]] to the egg. After [[Fertilisation|syngamy]] (joining of the sperm and egg cell), the zygote develops into an embryo (young sporophyte). More than one embryo is usually initiated in each gymnosperm seed. The mature seed comprises the embryo and the remains of the female [[Gametophyte#Seed plants|gametophyte]], which serves as a food supply, and the [[Seed-coat|seed coat]].<ref name="Walters1996">{{Cite book| last = Walters | first = Dirk R Walters Bonnie By| year = 1996| title = Vascular plant taxonomy| page = [https://archive.org/details/vascularplanttax00walt/page/124 124]| url = https://archive.org/details/vascularplanttax00walt| url-access = registration | quote = Gymnosperm seeds. | isbn = 978-0-7872-2108-9| publisher = Kendall/Hunt Pub. Co.| location = Dubuque, Iowa}}</ref>
Gymnosperms ordinarily reproduce by [[sexual reproduction]], and only rarely express parthenogenesis.<ref name
==Genetics==
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