Mold on surface of jelly—(Top) Ingmar Holmasen, (bottom) Stephen Collins

In biology, a conspicuous mass of mycelium and fruiting structures produced by various fungi (kingdom Fungi; see fungus). Molds of the genera Aspergillus, Penicillium, and Rhizopus are associated with food spoilage and plant diseases, but some have beneficial uses, such as in the manufacture of antibiotics (e.g., penicillin) and certain cheeses. Neurospora, or orange bread mold, has been invaluable in the study of genetics. Water molds (phylum Oomycota, kingdom Chromista) live in fresh or brackish water or wet soils, absorbing dead or decaying organic matter. See also slime mold.

This entry comes from Encyclopædia Britannica Concise.
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