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[[Image:Mature sporangium of a Mucor sp. fungus PHIL 3960 lores.jpg|thumb|200px|Mature sporangium of a ''[[Mucor]]'' mold]]
[[Image:XN Polytrichum spec.jpg|thumb|200px|Moss sporangia (capsules)]]
[[Image:Fern Sori.JPG|thumb|200px|Sporangia (sori) on a fern leaf]]
[[Image:Equisetum arvense sporangia.jpg|thumb|200px|''Equisetum arvense'' [[strobilus]] cut open to reveal sporangia]]
A '''sporangium''' (pl., '''sporangia''') is a [[plant]] or [[fungus|fungal]] structure producing and containing [[spore]]s. Sporangia occur on [[Flowering plant|angiosperms]], [[gymnosperm]]s, [[fern]]s, [[fern allies]], [[moss]]es, [[Algae|alga]]e, and [[Fungus|fungi]].
'''Microsporangia''' are the structures on the stamens of [[flower]]s called [[anther]]s, and the pollen-producing structures on the '''microsporophylls''' of male [[Conifer cone|conifer cone]]s.
'''Megasporangia''' are the comparable "female" structures on these plants, associated with the flower [[carpel]] and the megasporangial cone.
On [[fern]]s, the mature plant is a sporophyte that develops sporangia, tiny, stalked sacs which contain '''''[[spore|meiospores]]''''', on all or just certain leaves (called '''sporophylls''' if sporangia are present).
In mosses, the little case that rises above the vegetative growth on a thin '''stalk''' is a sporangium often called a ''capsule'' that, as in ferns, produces meiospores. This [[sporophyte|sporophytic]] ([[diploid]]) growth arises out of the [[gametophyte|gametophytic]] ([[haploid]]) [[archegonium]] after the ovum is fertilized. The sporophyte initially has some [[chlorophyll]], but later turns brown and becomes dependent upon the gametophyte for nutrition, which is absorbed through the '''foot''' (base of the stalk), embedded in the archegonial tissues.
Categorized based on developmental sequence, '''''eusporangia''''' and '''''leptosporangia''''' are differentiated in the vascular plants. In a leptosporangium, found only in ferns, development involves a single initial cell that becomes the stalk, wall, and spores within the sporangium. There are around 64 spores in a leptosporangium. In a eusporangium, characteristic of all other vascular plants and some primitive ferns, the initials are in a layer (i.e., more than one). A eusporangium is larger (hence contain more spores), and its wall is multi-layered. Although the wall may be stretched and damaged, resulting in only one cell-layer remaining.
A cluster of sporangia that have become fused in development is called a '''synangium'''. This structure is most prominent in ''[[Psilotum]]'' and [[Marattiaceae]] such as ''[[Christensenia]]'', ''[[Danaea]]'' and ''[[Marattia]]''.
==See also==
*[[archegonium]]
*[[antheridium]]
*For [[bacterium|bacteria]]-related information see [[endospore]]
[[Category:Plant anatomy]]
[[Category:Fungal morphology and anatomy]]