Fungi are important group of organisms as they are the decomposers of the biosphere. It brings about the decomposition of the organic matter together with the bacteria their by re-cycling of nutrients. Some of the fungal members are involved in the nitrogen fixation e.g. Saccharomyces. And some others play an active role in the soil formation e.g. Rhizopus, Aspergillus etc. Several fungi are there which causes rotting of wood by degradation of cellulose and lignin e.g. Polyporus, Ganoderma. Fungi also form mutualistic associations with the other organisms, such as Lichens and Mycorrhizae.
