Cellular Respiration

Definition: Cellular Respiration

Cellular Respiration

Noun

1. Bodily process whereby oxygen in the blood is absorbed by the cells of the body and carbon dioxide is absorbed by the blood as a waste product to be transported to the lungs.

Specialty Definition: Cellular respiration

(From Wikipedia, the free Encyclopedia)

Cellular respiration is, in its broadest definition, the process in which the chemical bonds of energy-rich molecules such as glucose are converted into energy usable for life processes. All forms of life except viruses carry out respiration. Oxidation of organic material — in a bonfire, for example — releases a large amount of energy rather quickly. The overall equation for the oxidation of glucose is:

C₆H₁₂O₆ + 6O₂ ⇒ 6CO₂ + 6H₂O + energy

In respiration, the process of oxidation is broken down into a large number of steps. These steps are catalysed by enzymes and coenzymes; each step releases a small amount of energy in the form of ATP. This process consists of two main steps: glycolysis, and pyruvate breakdown.

Glycolysis
Glycolysis does not need oxygen in any of its steps. It is a metabolic pathway that is found in all living organisms and it probably evolved billions of years ago before the Earth's atmosphere contained oxygen.
It is the process that converts one molecule of glucose into two molecules of pyruvate.
It releases energy in the form of two molecules of ATP.
It takes place in the cytoplasm of the plant or animal cell.

Breakdown of Pyruvate
There are now two ways to break down the resulting pyruvate:

Aerobic Respiration

Aerobic respiration requires oxygen. It is the preferred method of pyruvate breakdown. It yields 36 ATP molecules, as well as carbon dioxide, and water. This makes for a total gain of 38 ATP molecules during cellular respiration. This takes place in the mitochondria of the cells.

Anaerobic Respiration
Anaerobic respiration doesn't require oxygen. In this process, the pyruvate is only partially broken down.
Fermentation (done by yeast and some types of bacteria) breaks the pyruvate down into ethanol, carbon dioxide, and water. It is important in bread making, brewing, and wine making.
Lactic acid fermentation breaks the pyruvate down into lactic acid, carbon dioxide, and water. It occurs in the muscles of animals when they need energy faster than the blood can supply oxygen. It also occurs in some bacteria. It is this type of bacteria that convert lactose into lactic acid in yoghurt giving it its sour taste.
Both ethyl alcohol and lactic acid contain chemical energy that can't be used by anaerobic respiration, making this an inefficient process. Anaerobic respiration releases a total of two ATP molecules (compare to the 38 of aerobic respiration).

See Also

respiration
tricarboxylic acid cycle

External links

A detailed diagram of glycolysis
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Cellular respiration."

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Synonym: Cellular Respiration

Synonym: internal respiration (n). (additional references)

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Crosswords: Cellular Respiration

English words defined with "cellular respiration": Otto Heinrich Warburg ♦ superoxide, superoxide anion ♦ Warburg. (references)

Specialty definitions using "cellular respiration": Thenoyltrifluoroacetone. (references)

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Frequency of Internet Expressions: Cellular Respiration

The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com.

Expression	Frequency per Day
cellular respiration	157
cellular respiration photosynthesis	14
aerobic cellular respiration	5
biology cellular respiration	4
Source: compiled by the editor from various references; see credits.

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Anagrams: Cellular Respiration

Scrabble® Enable2K-Verified Anagrams
	Words within the letters "a-a-c-e-e-i-i-l-l-l-n-o-p-r-r-r-s-t-u"
	-5 letters: counterrallies, proletarianise, resurrectional, ultraprecision.
Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro.

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