What are hyphae?

Hyphae are the thread-like structures of a fungal mycelium that form a network of feeding structures to help nourish and feed the fungus.  In a puffball mushroom, for example, there are tightly-packed hyphae in the stalk of the mushroom body, and loosely-packed hyphae in the ground surrounding the mushroom body.  The network of hyphae secure important water and nutrients for the fungal body.  It works opposite the way our digestive system works, where we ingest food, then break it down through a series of mechanical and chemical steps.  The fungus sinks the hyphae into the food source, then emits digestive enzymes into the food source.  When the food has been chemically digested, it is absorbed by the hyphae and fed to the body of the fungus.  Hyphae function as digestive structures that supply the fungus with water and nutrition.