<P> There are two functionally different classes of disaccharides: </P> <Ul> <Li> Reducing disaccharides, in which one monosaccharide, the reducing sugar of the pair, still has a free hemiacetal unit that can perform as a reducing aldehyde group; cellobiose and maltose are examples of reducing disaccharides, each with one hemiacetal unit, the other occupied by the glycosidic bond, which prevents it from acting as a reducing agent . </Li> <Li> Non-reducing disaccharides, in which the component monosaccharides bond through an acetal linkage between their anomeric centers . This results in neither monosaccharide being left with a hemiacetal unit that is free to act as a reducing agent . Sucrose and trehalose are examples of non-reducing disaccharides because their glycosidic bond is between their respective hemiacetal carbon atoms . The reduced chemical reactivity of the non-reducing sugars in comparison to reducing sugars, may be an advantage where stability in storage is important . </Li> </Ul> <Li> Reducing disaccharides, in which one monosaccharide, the reducing sugar of the pair, still has a free hemiacetal unit that can perform as a reducing aldehyde group; cellobiose and maltose are examples of reducing disaccharides, each with one hemiacetal unit, the other occupied by the glycosidic bond, which prevents it from acting as a reducing agent . </Li> <Li> Non-reducing disaccharides, in which the component monosaccharides bond through an acetal linkage between their anomeric centers . This results in neither monosaccharide being left with a hemiacetal unit that is free to act as a reducing agent . Sucrose and trehalose are examples of non-reducing disaccharides because their glycosidic bond is between their respective hemiacetal carbon atoms . The reduced chemical reactivity of the non-reducing sugars in comparison to reducing sugars, may be an advantage where stability in storage is important . </Li>

What kind of bond is formed between 2 monomers of sugar to create a di- or poly-saccharide