Mouldy strawberries. View of mould growing on the surface of strawberries, vegetables and bread. Mould is the fuzzy, cobweb-like growth produced on organic matter by several different types of fungi. The moulds here began as microscopic, airborne spores. On contact with the moist surface of the fruit and vegetables they germinated. Rapid spread formed the mycelia (fungal bodies) made up of fine networks of filaments (hyphae). Root-like rhizoids (unseen) penetrate downwards into the food, secreting enzymes and absorbing water and sugars. The lack of mould on the jam (at right) is indicative of the preservative action of its high sugar content.