White bread mould. Coloured scanning electron micrograph (SEM) of the fruiting bodies of two types of mould growing on white bread. The moulds are Penicillium sp. and Mucor mucedo. Spores from these moulds circulate freely in the air. On a favourable medium, they germinate and form an extensive network of threads (hyphae) that absorb food for growth and spore production. The Mucor spores are borne in the sac-like bodies seen, which are called sporangia. The Penicillium spores, known as conidia, are borne directly on special hyphae called conidiophores. Magnification: x40 at 6x7cm size.