Fungi is the plural word for "fungus". A fungus is a eukaryotic organism. Yeasts, moulds and mushrooms are examples of fungi. The study of fungi is called mycology. Like animals, humans and most bacteria, all fungi are heterotrophs. Most fungi are large enough to be seen with the eye. However, some are microscopic organisms and the study of microscopic fungi is encompassed by the field of microbiology. Some microscopic fungi, for example yeast, are used in the food and drink industry to produce bread, beer and wine. Fungi are important in the pharmaceutical and biotechnology industries and are used in the production of antibiotics and various enzymes. || What are fungi and where can they be found? Growths can be single celled or exceptionally complex multicellular living beings. They are found in pretty much any environment yet most live on the land, primarily in soil or on plant material instead of in ocean or crisp water.