1. 1. Ecology of Fungi 21.3
   
2. 2. Saprobe
   Organism that obtains food from decaying organic matter.
   
3. 3. Lichen
   Symbiotic association between a fungus and a photosynthetic organism.
   
4. 4. Mycorrhiza
   Symbiotic association of plant roots and fungi.
   
5. 5. Key Concept
   Fungi play an essential role in maintaining equilibrium in nearly every ecosystem, where they recycle nutrients by breaking down the bodies and wastes of other organisms.
   
6. 6. Key Concept
   Some fungi form symbiotic relationships in which both partners benefit. Two such mutualistic associations, lichens and mycorrhizae, are essential to many ecosystems.