1.1.9 Cellulose

Cellulose is a structural polysaccharide found in the cell walls of plants. It is made up of long, unbranched chains of beta-glucose molecules, which are linked together by glycosidic bonds.

• The beta-glucose molecules are arranged in a straight, linear fashion, which allows them to form microfibrils. These microfibrils are strong fibres that provide structural support.
• The cellulose chains are held together by hydrogen bonds, which create strong cross-linkages between them. This adds to the strength and rigidity of the plant cell walls.

Cellulose plays a crucial role in maintaining the shape and structure of plant cells. It helps prevent the cell wall from bursting under osmotic pressure by exerting inward pressure. This inward pressure stops too much water from entering the cell, keeping the plant cells turgid (firm) and rigid. This rigidity helps the plant to maintain its shape and maximises the surface area available for photosynthesis.