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Line 1: {{more footnotes\|date=December 2013}} A '''sporophyll''' is a [[leaf]] that produces [[spore]]s. Sporophylls are part of the [[diploid]] [[sporophyte]] generation, and the spores are produced by [[meiosis]] and will germinate to produce [[haploid]] [[gametophyte]]s. The spores are born in [[sporangia]], which can take various forms in different kinds of plants. The sporophylls themselves also vary greatly in appearance and structure, and may or may not look similar to the [[trophophyll]]s--leaves which only undergo [[photosynthesis]] to produce [[sugar]]s, never producing spores. In more primitive plants, such as [[lycophyte]]s and [[fern]]s, the sporophylls and trophophylls are both green and photosynthesize, and usually look very similar to each other. In more advanced plants, such as [[seed plant]]s--and a few unusual primitive plants such as [[Equisetum]]--the sporophylls and trophophylls are very different from each other. For instance, in [[pine]]s the sporophylls are modified to form both the woody [[bract]]s of pine cones (often called "ovuliferous scales") as well as the smaller, non-woody bracts of the pollen cones. In flowers the sporophylls are even further modified, and are represented by the [[stamen]]s and [[carpel]]s. {{Distinguish\|Sporophyte}} [[File:Fern-frond-sori.jpg\|thumb\|right\|The sporophyll of a fern. It is a fertile leaf bearing reproductive structures.]] A '''sporophyll''' is a [[leaf]] that bears [[sporangia]]. Both [[microphylls and megaphylls]] can be sporophylls. In [[heterosporous]] plants, sporophylls (whether they are microphylls or megaphylls) bear either megasporangia and thus are called '''megasporophylls''', or [[microsporangia]] and are called '''microsporophylls'''. The overlap of the prefixes and roots makes these terms a particularly confusing subset of botanical nomenclature. Sporophylls vary greatly in appearance and structure, and may or may not look similar to sterile leaves. Plants that produce sporophylls include: Small foliaceous structures bearing the sporangia in brown algae of the genus [[Alaria]] are also called "sporophylls", though structurally they are quite different from the sporophylls of [[vascular plant]]s. ''[[Alaria esculenta]]'', a brown alga which shows sporophylls attached near the base of the alga.<ref>Dickson, Carola I. 1963. ''British Seaweeds''. The Kew Series.</ref> ~~[[de:Sporophyll]]~~ [[Category:Botany]]▼ [[Lycophyte]]s, where sporophylls may be aggregated into [[strobilus\|strobili]] (''Selaginella'' and some ''Lycopodium'' and related genera) or distributed singly among sterile leaves (''[[Huperzia]]''). Sporangia are borne in the axil or on the adaxial surface of the sporophyll. In heterosporous members, megasporophylls and microsporophylls may be intermixed or separated in a variety of patterns. [[Fern]]s, which may produce sporophylls that are similar to sterile fronds or that appear very different from sterile fronds. These may be non-photosynthetic and lack typical pinnae, e.g. ''[[Onoclea sensibilis]]''. [[Cycad]]s produce strobili, both pollen-producing and seed-producing, that are composed of sporophylls. ''[[Ginkgo]]'' produces microsporophylls aggregated into a pollen strobilus. Ovules are not born on sporophylls {{Citation needed\|reason=the structure that carries the seed and arillus of Ginko can and has been interpreted as a leave (This means that Ovules are in Ginko born on megasphorophylls), why should this be wrong now?\|date=October 2017}}. [[Gymnosperm]]s, like ''Ginkgo'' and cycads, produce microsporophylls, aggregated into pollen strobili. However, unlike these other groups, ovules are produced on cone scales, which are modified shoots rather than sporophylls. Some plants do not produce sporophylls. Sporangia are produced directly on stems. ''[[Psilotum]]'' has been interpreted as producing sporangia (fused in a synangium) on the terminus of a stem. ''[[Equisetum]]'' always produce strobili, but the structures bearing sporangia (sporangiophores) have been interpreted as [[Aerial stem modification\|modified stems]]. The sporangia, despite being recurved are interpreted as terminal. [[Gnetophyte]]s produce both compound pollen and seed strobili. ==References== * C.Michael Hogan. 2010. [http://www.eoearth.org/article/Fern ''Fern''. Encyclopedia of Earth. National council for Science and the Environment]. Washington, DC {{botany}} [[Category:Plant morphology]] [[Category:Plant reproduction]] ▲[[Category:~~Botany~~Leaves]] {{Reflist}}