An ascus is the sexual spore-bearing cell produced in ascomycete fungi. On average, asci normally contain 8 ascospores, produced by a meiotic cell division followed, in most species, by a mitotic cell division. However, asci in some genera or species can number 1 , 2, 4, or multiples of four. In a few cases, the ascospores can bud off conidia that may fill the asci with hundreds of conidia, or...