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A microsporangium (pl. microsporangia) is a sporangium that produces microspores that give rise to male gametophytes when they germinate. Microsporangia occur in all vascular plants that have heterosporic life cycles, such as seed plants , spike mosses and the aquatic fern genus Azolla .
The microspore has three different types of wall layers. The outer layer is called the perispore, the next is the exospore, and the inner layer is the endospore.The perispore is the thickest of the three layers while the exospore and endospore are relatively equal in width.
In biology, the theca of follicle can also refer to the site of androgen production in females. The theca of the spinal cord is called the thecal sac, and intrathecal injections are made there or in the subarachnoid space of the skull.
A sporangium (from Late Latin, from Ancient Greek σπορά (sporá) 'seed' and ἀγγεῖον (angeîon) 'vessel'); pl.: sporangia) [1] is an enclosure in which spores are formed. [2]
Within the stamen, the microsporangium forms grains of pollen, surrounded by a protective microspore, which form the male gametophyte. Within the carpel the megasporangium form the ovules, with its protective layers in the megaspore, and the female gametophyte. Unlike the male gametophyte, which is transported in the pollen, the female ...
The sporophyll of a fern. It is a fertile leaf bearing reproductive structures. In botany, a sporophyll is a leaf that bears sporangia.Both microphylls and megaphylls can be sporophylls.
Such plants typically give rise to the two kind of spores from within separate sporangia, either a megasporangium that produces megaspores or a microsporangium that produces microspores. In flowering plants, these sporangia occur within the carpel and anthers, respectively.
Stamen is the Latin word meaning "thread" (originally thread of the warp, in weaving). [8]Filament derives from classical Latin filum, meaning "thread" [8]; Anther derives from French anthère, [9] from classical Latin anthera, meaning "medicine extracted from the flower" [10] [11] in turn from Ancient Greek ἀνθηρά (anthērá), [9] [11] feminine of ἀνθηρός (anthērós) meaning ...