What is mycelium?

• A. A network of hyphae
• B. A type of spore
• C. A photosynthetic organ
• D. A root-like structure

Answer: (A)

The concept being tested is that mycelium is the filamentous feeding network of a fungus. It is formed by a mass of thread-like structures called hyphae growing together. This hyphal network—the mycelium—spreads through the surrounding material, secreting enzymes to break down complex substances and then absorbing the resulting nutrients. A spore is a reproductive unit, not the growth form you see spreading as food is broken down. Mycelium isn’t a photosynthetic organ; fungi don’t photosynthesize. And while hyphae can penetrate, anchor, or spread through substrates, the defining idea is the network of hyphae that constitutes the mycelium.