Monosaccharide, Disaccharide, Polysaccharide. by edith noriega on Prezi
The simplest sugars are monosaccharides. Glucose (grape sugar) is the sugar of the surface animals. Galactose, fructose, Ribose— the sugar of DNA fame. A monosaccharide is a simple sugar whereas a polysaccharide consists of chains of monosaccharides or disaccharides bonded together. Both types of. This linkage motif contrasts with that for α(1→4)-glycosidic bonds The difference between the unmodified and modified forms can be GlcNAc, or NAG ) is a monosaccharide derivative of glucose.
These are unbranched carbon chains where all the carbon atoms are linked by single bonds. The family of the monosaccharide consists of two members which are Aldoses and Ketoses. If the carbonyl group when one of the carbon atoms of open-chain is linked by double bonds to any of the oxygen atoms is at the end of the carbon chain than the monosaccharide is an aldose, but if the carbonyl group is at other position of the carbon chain than the monosaccharide is called as ketose.
The other carbon atoms in the carbon chains have the hydroxyl group.
Tetroses, pentoses, hexoses, and heptoses are the monosaccharides with four, five, six, and seven carbon atoms respectively in their backbone of structures. All the monosaccharides occur in optically active isomeric forms as they contain one or more asymmetric chiral carbon atoms, except the dihydroxyacetone.
The Differences Between Monosaccharides & Polysaccharides | Sciencing
They have their general formula is CH2O n, where n represents the number of carbon atoms present. D-form is found in naturally occurring monosaccharides and L form is found in synthetically produced monosaccharides ones. These both forms have different properties. Some common naturally occurring monosaccharides are Glucose, fructose, mannose, and galactose.
Examples of foods that contain a lot of fruit juices, candies, sweet wines, honey, etc. Polysaccharides are also called as glycans. They are the long chains of monosaccharides units bonded together by glycosidic linkages which can be further hydrolyzed to give oligosaccharides or monosaccharides. These are the polymers of high molecular weight. They differ from each other in the type of bonding, the length of the chains, recurring of monosaccharide units and degree of branching.
Their structure varies from a linear to the highly branched chain. Glucose, galactose, fructose, and mannose are the few common polysaccharides. These are of two types Homopolysaccharides and Heteropolysaccharides. Homopolysaccharide contains a uniform species, it means all the monosaccharides units are of the same type.
Difference Between Monosaccharides Disaccharides and Polysaccharides
Whereas heteropolysaccharide contains two or more different type of monosaccharides units. For example, the aldohexose glucose may form a hemiacetal linkage between the hydroxyl on carbon 1 and the oxygen on carbon 4, yielding a molecule with a 5-membered ring, called glucofuranose.
The same reaction can take place between carbons 1 and 5 to form a molecule with a 6-membered ring, called glucopyranose.
Cyclic forms with a 7-atom ring the same of oxepanerarely encountered, are called septanoses. For many monosaccharides including glucosethe cyclic forms predominate, in the solid state and in solutions, and therefore the same name commonly is used for the open- and closed-chain isomers.
Thus, for example, the term "glucose" may signify glucofuranose, glucopyranose, the open-chain form, or a mixture of the three. Cyclization creates a new stereogenic center at the carbonyl-bearing carbon The -OH group that replaces the carbonyl's oxygen may end up in two distinct positions relative to the ring's midplane.
The molecule can change between these two forms by a process called mutarotation, that consists in a reversal of the ring-forming reaction followed by another ring formation. Pyranose forms of some pentose sugars. Pyranose forms of some hexose sugars. Disaccharides[ edit ] There are two different types of disaccharides: Cellobiose and maltose are examples of reducing disaccharides. Sucrose and trehalose are examples of non-reducing disaccharides.
This is how animals use plant starches to make glucose for metabolism.
Principles of Biochemistry/The Carbohydrates: Monosaccharides, Disaccharides and Polysaccharides
The base monosaccharide of cellulose is glucose. The straight cellulose molecules make up rows in a stable form via the weak but prevalent hydrogen bonds between them. Made by plants, fungi and algae, cellulose provides the rigid structure of plant cell walls, which also protect against diseases. Many animals cannot digest cellulose, but those that can use intestinal micro-organisms and enzymes for the task.
Fermentation occurs in the colon of other animals and humans that cannot digest cellulose. Animals produce a similar polysaccharide, chitin, made from a modified monosaccharide. Both cellulose and chitin make up compact energy storage units. Another polysaccharide, glycogen, can be broken down from its compact form quickly into its constituent glucose monosaccharides.
Humans store glycogen as a rapid energy source in the liver and muscles. Pectins, arabinoxylans, xyloglucans and glucomannans represent additional complex polysaccharides. Monosaccharides are soluble in water, but many polysaccharides have poor water solubility in water. Polysaccharides can form gels, depending on their solubility.
This is why they are often used to thicken foods.