Fungi have cells with nuclei. Their cell walls contain chitin, unlike the cell walls of plants, which contain cellulose. These and other differences show that the fungi form a single group of related organisms, called the Eumycota or Eumycetes. They share a common ancestor and are monophyletic group.
Fungi reproduce both sexually and asexually. Some fungi grow mushrooms: these are fruiting bodies. Under the cap there are gills; the gills bear spores that will disperse, and may develop into new fungi. Otherwise, fungi use a sporangium to bear asexual spores by mitosis, or sexual spores by meiosis. The spores are haploid.
Symbiosis means living together. Lichens are a symbiosis between a fungus and an alga or bacterium. In this partnership the algal cells live inside the fungus tissue. The end result is a new mat-like life-form which clings to rock and other surfaces. About 20% of all fungi are lichenized.
Another important kind of symbiosis is mycorrhiza. This is when a fungus lives inside plant roots; most trees have mycorrhizal roots, and so do many crop plants. Both sides benefit in this arrangement.
Some fungi cause crop diseases; others cause serious disease in humans. Some are highly poisonous: never eat a mushroom picked in the wild unless you know what you are doing.
- Edible fungi are widely used as human food. Certain types of cheese need a fungal species to be added. The fungi give a unique flavor and texture to the cheese.
- Some fungi produce psychotropic (mind-altering) substances. Several species, most notably Psilocybin mushrooms (colloquially known as magic mushrooms), are taken for their psychedelic properties, so they are illegal in many countries around the world.
- In modern times, some fungi (for example, Penicillin) have been used as a source of antibiotics. The antibiotics are produced by many fungi as a natural defence against bacteria.
- Jennings D.H. & Lysek G. 1996. Fungal biology: understanding the fungal lifestyle. Guildford, UK: Bios Scientific Publishers . ISBN 978-1-85996-150-6
- Kirk P.M. et al 2008. Dictionary of the fungi, 10th ed. Wallingford, UK: CAB. ISBN 0-85199-826-7
- Margulis L. Schwartz K.V. & Dolan M. 1999. Diversity of life: the illustrated guide to the five kingdoms. Jones & Bartlett, Sudbury MA.