|MadSci Network: Microbiology|
Mold is a very generalized term, but technically refers to the asexual stage of a fungus, predominantly "Ascomycota". Many molds grow on bread, such as Penicillium, so your question is a broad one. When a life cycle of a fungus is figured out, the mold or asexual part of that lifecycle, is grouped with the sexual part in terms of naming the organisim. Some molds have not been "linked up" with their sexual counterparts but more are being discovered all the time. Many of these are considered in the larger group Hyphomycetes. Most molds are Hyphomycetes and a fewer number are Coelomycetes. So in answer to your question, most molds you will find on breads will be in the groups: Zygomycotes, Ascomycetes and Hyphomycetes.
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