Define the following terms :

(i) Glycosidic linkage

(ii) Invert sugar

(iii) Oligosaccharides

(i) We find α-glycosidic linkage present in maltose.

In maltose, two glucose units are joined by a glycosidic linkage between the α-anomeric form of C-1 on one glucose unit and the hydroxyl oxygen atom on C-4 of the adjacent glucose unit. Such a linkage is called α-1,4-glycosidic bond.

(ii) Hydrolysis of sucrose breaks the glycosidic linkage thereby converting sucrose into glucose and fructose. There is a change in the sign of rotation from dextro(+) to laevo(-) due to this inversion, the product obtained is known as invert sugar. The hydrolysis of sucrose results in a mixture having equal parts of glucose and fructose.

(iii) Oligosaccharides are a type of saccharides (carbohydrates having general formula C_nH_2nO_n) which contain small number (around 3-10) of monosaccharide (simplest form of sugar).

Cell recognition and cell binding are some important functions performed by oligosaccharides.