U.S. Micro-Solutions, Inc. Fungal Library
Fungi are eukaryotic organisms which include unicellular yeasts, multicellular molds, and macroscopic varieties such as mushrooms. The colony of mold consists of long filaments called hyphae through which dissolved organic matter is absorbed. When environmental conditions are suitable, the hyphae grow, intertwine, and form a mass called a mycelium.
The portion of mycelium concerned with obtaining nutrients is called the vegetative mycelium; the portion concerned with reproduction is called reproductive or aerial mycelium. The aerial mycelium as the name implies, projects above the surface of the medium on which the fungus is growing and often bears the reproductive spores. Spores are of key importance in the fungal identification process.