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A polar bear is just one example of an organism that uses respiration to gain biochemical energy. Respiration occurs in all other animals too.
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Respiration

Respiration is the name of the general process by which living organisms convert sugars and oxygen into biochemical energy. The process occurs in all organisms, including animals, plants, fungi, and bacteria (though in some cases other electron acceptors, like nitrate, are substituted for the oxygen). During respiration, carbohydrates are broken down, and the energy stored in the carbohydrates' bonds is used to produce ATP and other high-energy compounds that can be used throughout the cell to fuel the different processes necessary to support life.

In addition to producing useful energy, respiration produces carbon dioxide and water as waste products. The overall equation for the process is given below:


The reverse of this process, used by autotrophs (self-feeders), is known as photosynthesis. During photosynthesis, energy from the Sun's rays is used by cells to produce carbohydrates, with oxygen made as a byproduct.


Last modified August 16, 2006 by Jennifer Bergman.

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