Fungus. Coloured scanning electron micrograph (SEM) of fungal cells found growing on damp blotting paper. The round structures are sporangia, which house the fungus' reproductive cells (spores). Hyphae are thread-like structures that form the mycelium, the vegetative part of the fungus that absorbs nutrients from its environment. Magnification: x 800 at 10 centimetres wide.