Mycology

The vegetative body of a fungus, consisting of a network of fine, thread-like filaments called hyphae. Mycelium is the primary structure through which fungi absorb nutrients from their environment and can extend over vast areas underground.

A mutualistic symbiotic association between fungal hyphae and plant roots, in which the fungus provides the plant with enhanced access to water and soil minerals while receiving carbohydrates produced by the plant through photosynthesis.

A reproductive unit produced by fungi that is capable of developing into a new organism. Spores can be produced sexually (e.g., ascospores, basidiospores) or asexually (e.g., conidia), and are typically microscopic and highly adapted for dispersal.

The process by which fungi break down complex organic compounds in dead organisms and waste material into simpler substances. Fungi are the only organisms capable of fully degrading lignin, the structural polymer that gives wood its rigidity.

The spore-bearing reproductive structure produced by a fungus, typically visible above ground. Fruiting bodies include mushrooms, brackets, puffballs, truffles, and cup fungi, and represent only a small fraction of the total fungal organism.

A long-chain polymer of N-acetylglucosamine that forms a major structural component of fungal cell walls. Chitin provides rigidity and protection, and its presence in fungal cell walls distinguishes fungi from plants, which use cellulose.

A composite organism formed by a stable mutualistic relationship between a fungus (the mycobiont, usually an ascomycete) and a photosynthetic partner such as a green alga or cyanobacterium (the photobiont). Lichens are not a single species but a symbiotic association.

A nutritional mode in which organisms obtain nutrients by secreting extracellular enzymes to digest dead or decaying organic matter externally and then absorbing the resulting soluble molecules. Most fungi are saprotrophs.

A metabolic process in which fungi, particularly yeasts, convert sugars into alcohol, carbon dioxide, or organic acids in the absence of oxygen. This process is fundamental to the production of bread, beer, wine, and many other food products.

The use of fungi (mycoremediation) to degrade or sequester environmental pollutants, including petroleum hydrocarbons, pesticides, heavy metals, and synthetic dyes. Fungi achieve this through their powerful extracellular enzyme systems.