Symbiotic Relationships Mutualism++ Commensalism+o Parasitism+- symbiont host

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A mutualistic relationship between legumes and soil bacteria in the genus Rhizobium. The Rhizobia can fix nitrogen gas when the symbiosis is achieved. They can't fix nitrogen in the free-living state, however!

Fixed nitrogen is obtained by the legume and the Rhizobium gets a nice place to live with all of the amenities!. This includes glucose, water and minerals. This is an extremely important relationship because Nitrogen is usually the most limiting element in terrestrial ecosystems

Inner nitrogen fixing bacteria

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Lichens are common primary colonizers of stressful habitats.

The algae supplies the organic carbon from photosynthesis, and the fungi ensures protection, and the supply of minerals and water.

mycelium + algae

Lichens- associations between algae and fungi mycelium algae -provides sugar from photosynthesis fungi -provide water, protection from UV rays, and a “home”. mutualisti c

Mycorrihizae- mutualistic fungi and plant roots mutualistic relationship between fungi and plant roots plant plant provides sugar for fungi. fungi fungi increases plants ability to absorb water and minerals like phosphorus.

Mycorrihizae- + fungus + plant

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++ Although termites can physically chew and ingest wood, they are incapable of chemically digesting cellulose into sugars. They rely on intestinal flagellates, Trichonympha spp. which are capable of digesting cellulose. These genera of flagellates reside in the hindgut of termites and provide nutrition for them. They are not found anywhere else in nature.

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+ plasmodium - human with malaria

+ worm- human/animal infected