The main structural component of plant cell walls is cellulose which is a type of carbohydrate made up of a long chain of glucose molecules (a polysaccharide).
Explanation:
The plant cell walls are composed of cellulose, which is a structural carbohydrate made up of a long chain of glucose molecules (β linked D-glucose units). It is a polysaccharide like starch, but the starch molecule is flexible and the cellulose molecule is rigid. Each of these polysaccharide chains is connected together by hydrogen bonds. Microfibrils are formed by arranging some of these polysaccharide chains in parallel arrays. Due to the presence of hydrogen bonds, the microfibrils are extremely tough and inflexible. This property of cellulose provides strength and rigidity to the plant cell walls.
