Martin, Arthur W. Department of Zoology, University of Washington, Seattle, Washington.
Last reviewed:September 2021
Show previous versions
- Physiological problems
- Other compounds
- Excretory structures
- Contractile vacuoles
- Nephrons and kidneys in vertebrates
- Excretion of nitrogenous wastes
- Related Primary Literature
- Additional Reading
The removal of excess material from a cell or a living organism. Excretion is the process by which organisms, chiefly animals, eliminate metabolic waste products and excess water. In general, the concept of excretion is quite broad. Therefore, the study of excretion is most often limited to the animal kingdom (Fig. 1). (Because of differences in physiology, excretion is not a major problem in the plant kingdom.) In addition, certain biological processes that could fall under the heading of excretion are typically studied together with other physiological mechanisms. For example, carbon dioxide is one of the chief products of the metabolism of cells, and special mechanisms have evolved in large animals for the transport of carbon dioxide in blood. However, the removal of carbon dioxide is considered to be a process of blood-gas transport. Similarly, the excretion of heat is studied as a mechanism of body-temperature regulation, whereas the excretion of salts is viewed as an osmoregulatory process. See also: Animal; Animal kingdom; Carbon dioxide; Osmoregulatory mechanisms; Respiration; Thermoregulation
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 10,000 highly qualified scientists and 46 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information