The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
A mutualism is a symbiosis where two or more species gain mutual benefit from their interactions, and suffer negative impacts when the mutualistic interactions are prevented from occurring. Mutualism is a form of symbiosis where the interactions are frequently obligatory, with neither species being capable of surviving without the other. A well-known example of mutualism is the relationship between certain species of algae or blue-green bacteria and fungi that results in organisms called lichens. The fungal member of the relationship provides a spatial habitat for the algae, which in turn provide energy from photosynthesis to the fungus. Mutualistic interactions are thought to be the origin of the many cell organelles like mitochondria and chloroplasts, which may have resulted from the acquisition of free-living phytoplankton and other single-celled organisms by host species. Both the incorporated cell and the host soon evolved so that neither could exist without the other.