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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] It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other groups form sporangia at some point in their life cycle.
In meiotic sporogenesis, a diploid spore mother cell within the sporangium undergoes meiosis, producing a tetrad of haploid spores. In organisms that are heterosporous, two types of spores occur: Microsporangia produce male microspores, and megasporangia produce female megaspores. In megasporogenesis, often three of the four spores degenerate ...
The main difference between spores and seeds as dispersal units is that spores are unicellular, the first cell of a gametophyte, while seeds contain within them a developing embryo (the multicellular sporophyte of the next generation), produced by the fusion of the male gamete of the pollen tube with the female gamete formed by the ...
The fungus produces a thick walled structure known as a winter sporangium. It is 25-75 μm in diameter and contains 200-300 spores. Sporangia are clustered into thin-walled sori. The motile life stage, zoospore is about 0,5 μm in diameter and has one posterior flagellum.
Mucor spores or sporangiospores can be simple or branched and form apical, globular sporangia that are supported and elevated by a column-shaped columella. Mucor species can be differentiated from molds of the genera Absidia , Rhizomucor , and Rhizopus by the shape and insertion of the columella, and the lack of stolons and rhizoids .
Some exosporic species produce micro- and megaspores in the same sporangium, a condition known as homoangy, while in others the micro- and megaspores are produced in separate sporangia (heterangy). These may both be borne on the same monoecious sporophyte or on different sporophytes in dioicous species.
A zygospore is a diploid reproductive stage in the life cycle of many fungi and protists.Zygospores are created by the nuclear fusion of haploid cells. In fungi, zygospores are formed in zygosporangia after the fusion of specialized budding structures, from mycelia of the same (in homothallic fungi) or different mating types (in heterothallic fungi), and may be chlamydospores. [1]
The sporangiospores are asexual mitospores (formed via mitosis), produced inside sporangia (thousands of spores) or sporangioles (single or few spores).They are released when mature by the disintegration of the sporangium wall, or as a whole sporangiole that separates from the sporangiophore.