Ascus

Spore-bearing cell in ascomycete fungi

An ascus (from Ancient Greek ἀσκός (askós) 'skin bag, wineskin'; pl.: asci) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or species can occur in numbers of one (e.g.

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