Question

Carbohydrates are broadly divided into monosaccharides, oligosaccharides and polysaccharides.
(a) Write one example each of monosaccharide and oligosaccharide.
(b) (i) Write any one method for the preparation of glucose.
(ii) What is peptide linkage?

Answer 1

a) Mono saccharides are commonly called as simple sugars. They are soluble in water and sweet to taste. They are composed of 3 to 7 carbon atoms. For example: glucose, fructose

Oligo saccharides: They are carbohydrates formed by the joining of 2 to 6 monosaccharide molecules. The bond formed between monosaccharides, is called glycosidic bond, e.g., lactose, maltose

b) i) Photosynthesis: Preparation of glucose

$6C{O}_2+12H_{2}O\to C_6{H}_{1}2O_6+9O_2$

ii) A peptide linkage (bond) is a chemical bond formed between two molecules (amino acids) when the carboxyl group of one molecule reacts with the amino group of the other molecule, which releases a m water molecule ($H_{2}O$). This is a dehydration occurs between amino acids.