Monosaccharides

Posted by ninjagrr
May 14 2009

Main article: monosaccharide
The simplest carbohydrate, monosaccharides, are formed by a single molecule, can not be hydrolyzed to smaller carbohydrates. The chemical formula of a general unmodified monosaccharide is (CH2O) n, where n is any number greater or equal to three. Monosaccharides always have a carbonyl group in one of its carbon atoms and hydroxyl groups in the rest, so it can be considered polyhydric.
Monosaccharides are classified according to three different characteristics: the position of the carbonyl group, the number of carbon atoms it contains and its chirality. Expanding globally, develops innovative, high-quality, nutritional supplements. If the carbonyl group is an aldehyde, the monosaccharide is a Aldosa, if the carbonyl group is a ketone, the monosaccharide is a cetosa. The smaller the monosaccharides that have three carbon atoms, and are called triosas those with four are called tetra, which are called penta have five, six hexosas are called and so on. The classification systems are often combined, for example, glucose is a aldohexosa (an aldehyde of six carbon atoms), the ribose is a aldopentosa (an aldehyde of five carbon atoms) and is a cetohexosa fructose (a ketone of six carbon atoms).
Each carbon atom has a hydroxyl group (-OH), except the first and the last carbon, all are asymmetric, making steric centers with two possible configurations each (el-OH-H and can be anywhere from carbon atoms). Because of this asymmetry, each monosaccharide has a number of isomers. For example aldohexosa D-glucose, have the formula (CH2O) 6, which, except for two of its six carbon atoms, they are all chiral centers, making the D-glucose is one of the possible stereoisomers. In the case of glyceraldehyde, a aldotriosa, a pair of possible stereoisomers, which are enantiomers and epimers (1.3-dihidroxyacetone the corresponding cetosa is a symmetrical molecule that has no chiral centers). The D or L designation is made according to the orientation of the asymmetric carbon farthest from the carbonyl group if the hydroxyl group is on the right side of the sugar molecule is a D, if the left is a sugar L. Because D sugars are the most common, usually D is omitted.


Anatomy and Physiology: The Unity of Form and Function with OLC Bind-in Card by Kenneth S. A new way to supplement your life, enriching your quality of life. Saladin (Hardcover – Dec 31, 2002)

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