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.
Producers, sometimes called primary producers, are organisms that make their own food. Because these organisms change relatively simple inorganic nutrients into more complex, energy-rich, organic forms, they are autotrophs. Thus, they do not need any environmental source of organic material. Producers include green plants, algae and some bacteria.
Producers can use either sunlight or chemicals from inorganic chemical reactions as their source of energy. The process of using sunlight to produce food is called photosynthesis. The vast majority of producers, including plants, algae and some bacteria, produce their food using photosynthesis. Producers that use chemicals from inorganic chemical reactions as their source of energy are using the process known as chemosynthesis. Chemosynthesis generally occurs where there is no sunlight for photosynthesis, and bacteria are the only organisms that carry out this process. For example, in the deep ocean at hydrothermal vents, chemosynthetic bacteria are the base of the food web. All other organisms in this ecosystem rely on the chemosynthetic bacteria for food.
Producers hold an extremely important position in food webs in every ecosystem on Earth. In fact, without producers, an ecosystem would not be self-sustaining; it would not be able to exist on its own without the introduction of materials from another ecosystem. Producers are at the base of all food webs. They produce the organic nutrients upon which all other organisms in the ecosystem depend. Without these producers, there would be no way of capturing energy from the sun or chemical reactions, and therefore no new energy or organic material would enter the food web. When producers are consumed by herbivores or omnivores, organic material from the producers, as well as the stored energy they contain, is passed on to all other levels of the food web.