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Carbohydrates - Types

Simple Carbohydrates (Monosaccharides) - These are used only for energy in living organisms. The chemical formula for all of them is C6H12O6. However, they are different in structure. Some examples of Monosaccharides are:

  • glucose - found in fruits and honey
  • fructose - also found in fruits and honey
  • galactose - produced by the hydrolisis of lactose, which is found in milk




Compound Carbohydrates (Disaccharides) - These are used by living organisms for energy. They are composed of two monosaccharides joined together by the process known as dehydration synthesis. In this process, one molecule loses one hydrogen atom, while the other loses one hydrogen atom and one oxygen atom. They fill in the gap by joining with each other. The reverse of this is hydrolysis, where water is added to break down a molecule into two or more simpler molecules. Disaccharides have the chemical equation C12H22O11. The reason it does not follow the 1:2:1 ration is, obiously, due to the H2O taken way from it. Some examples of disaccharides are:

  • maltose - composed when two glucose molecules join together
  • sucrose - composed when one glucose molecule joins a fructose molecule; sucrose is commonly known as "table sugar"
  • lactose - composed when one glucose molecule joins a galactose molecule; also known as Milk sugar

Complex Carbohydrates (Polysaccharides) - Both monosaccharides and dicaccharides are used only for energy. Polysaccharides differ in that aspect. While animals still use it for energy, plants use it for energy and structure. Another difference is that while monosaccharides can be used for energy immediately, and disaccharides can be used for energy fast, because they can be broken down quickly, polysaccharides are used to store energy. These are the different polysaccharies:

  • cellulose (Fibre) - cellulose is a special kind of carbohydrate; found only in plants, and it's found in the cell wall; it helps the plant keep a strong structure; humans can't digest fibre; it is an important part of a healthy diet, because it helps clean up the digestive tract.
  • starch - starch is the energy storage molecule of plants; formed by chains of glucose.
  • glycogen - glycogen is the energy storage molecule of animals; formed by branched chains of glucose; humans store small ammounts of glycogen in the liver and muscles; created when there are high blood sugar levels; the pancreas secretes insulin, which stimulates the creation of gycogen from glucose

This article is courtesy of Wiki Books at Wiki Books

 


 


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Note that the contents here are not presented from a medical practitioner, and that any and all health care planning should be made under the guidance of your own medical and health practitioners. The content within only presents an overview of the topics and does not replace medical advice from a professional physician.

Where I have listed the nutritional contents of foods, that information is from the U.S. Department of Agriculture, Agricultural Research Service. 2005. USDA National Nutrient Database for Standard Reference, Release 18. Nutrient Data Laboratory Home Page.

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