Chapter 23, Problem 56A

Interpretation Introduction

Interpretation:

The molecular structures of cellulose and starch should be contrast and compared with each other.

Concept introduction:

A biological molecule which consists of carbon, hydrogen and oxygen is known as saccharide or carbohydrate. The general formula of saccharide is ${{\text{(CH}}_{\text{2}}\text{O)}}_{\text{n}}$.

Saccharides (sugar) are classified as: monosaccharides, disaccharides and polysaccharides.

Monosaccharides are defined as a simpler carbohydrate which contains one sugar molecule and can’t ne hydrolysed into smaller carbohydrate.

Disaccharides are defined as a saccharide which contains two sugar molecules that is when two monosaccharides are linked by glycosidic bonds. It is a double ring structure.

Polysaccharides are defined as a saccharide which contains many units of sugar molecules that is more than two monosaccharides are linked by glycosidic bonds.

Explanation of Solution

Starch consists of many units of monosaccharide as it is a polymeric carbohydrate which consists of glucose units linked with glycosidic bonds.

Cellulose consists of many units of monosaccharide or sugar as it is a polymeric carbohydrate which consists of various sugar units linked with glycosidic bonds.

The structures of both cellulose and starch are similar as both contains similar ring structures consist of carbon atoms, hydrogen atoms and oxygen atoms. Both starch and cellulose consist of ether bond.

According to the given structures, cellulose is an unbranched structure or a linear molecule whereas the starch is not a linear molecule or branched structure.