In a polysaccharide, the individual monosaccharides are linked by a glycosidic bond or ether linkage. Inulin is a polymer of fructose. It is a storage polysaccharide of roots and tubers of Dahlia and related plants. Inulin is not metabolized in the human body and is readily filtered through the kidney. It is therefore used in the testing of kidney function.
Two amino acids can join through an amino group of one and carboxylic group of the other forming peptide bond by loss of water molecule. Insulin is a peptide hormone made up of two chains A and B, having 21 and 30 amino acids, respectively.