Question

Which bond is present between adjacent glucose units in polysaccharides?

Answer 1

Hint: Polysaccharides are major classes of biomolecules that have long chains of carbohydrate molecules, which are composed of various smaller monosaccharides. It can either be a homopolysaccharide or a heteropolysaccharide with respect to the type of the monosaccharides. Polysaccharides can be a straight chain of monosaccharides or they can be branched, known as a branched polysaccharide.

Complete answer:
In a polysaccharide, adjacent glucose units are joined by a glycosidic bond. This bond is formed by the process of dehydration. A glycosidic bond or glycosidic linkage is a form of covalent bond that combines a carbohydrate molecule to another group, which may or may not be another carbohydrate. A glycosidic bond is a bond that is present in disaccharides and polysaccharides. This is a bond that is formed between two adjacent monosaccharides. Elimination of a water molecule accompanies the formation of a glycosidic bond as well.

A glycosidic bond is formed between the hemiacetal or the hemiketal group of a saccharide or a molecule derived from a saccharide and the hydroxyl group of some compound like an alcohol. A substance containing a glycosidic bond is known as a glycoside.

Note: Polysaccharides function as an important source of energy in the animal cell and forms a structural component of the plant cell. An ester bond is present in a nucleotide between a phosphate and a pentose sugar molecule whereas peptide bonds are present between successive amino acids in a protein molecule and hydrogen bonds are present between nucleotides on the opposite strands of a DNA molecule.