POLYSACCHARIDES

1. If many monosaccharides are joined together through condensation, a polysaccharide is formed
2. Polysaccharides may consist of hundreds or even thousands of monosaccharide units
3. Examples of polysaccharides:
4. Starch – storage material in plants
5. Glycogen is a storage carbohydrate in animals like starch, but has longer chains
6. Isulin – a storage carbohydrate in some plants e.g. Dahlia
7. Cellulose – structural carbohydrate in plants
8. Chitin – forms exoskeleton in arthropods

Importance and Functions of Polysaccharides

• They are storage carbohydrates – starch in plants glycogen in animals
• They are hydrolysed to their contituent monosaccharide units and used for respiration
• They form structural material e.g. cellulose makes cell walls
• Cellulose has wide commercial uses e.g.
• Fibre in cloth industry
• Cellulose is used to make paper
• Carbohydrates combine with other molecules to form important structural compounds in living organisms

Examples are:

Pectins: Combine with calcium ions to form calcium pectate

Chitin: Combine with (NH) group

Makes the exoskeleton of arthropods, and walls of fungi.

Also See:

PROCESS OF PHOTOSYNTHESIS

NUTRITION IN PLANTS

BIOLOGY PRACTICAL

ACTIVE TRANSPORT

WATER RELATIONS IN PLANT AND ANIMAL CELLS