Other Notify  ·  RSS  ·  Backlinks  ·  Source Relationships in Ecosystems An ecosystem is a natural unit consisting of all plants, animals and micro-organisms ( biotic factors) in an area functioning together with all of the non-living physical ( abiotic ) factors of the environment. http://www.bbc.co.uk/schools/gcsebitesize/img/bioaktree.jpg In previous lessons you examined