Which substance is the main constituent of the cell wall in most plants, particularly valued for paper production?

Cellulose is the main constituent of the cell wall in most plants, and it is especially valued for paper production due to its structural properties. It provides rigidity and strength to the plant cell walls, making it a critical component for the integrity of plant tissues. The long, linear chains of glucose molecules that make up cellulose allow for extensive hydrogen bonding, which results in a tough and resistant material. In paper production, cellulose pulp is the primary raw material, as it can be processed to create strong and durable paper products.

Starch, while also a polysaccharide like cellulose, serves primarily as an energy storage molecule in plants rather than a structural one. Lignin, another substance found in plant cell walls, plays a role in providing additional strength but is not the main component. Pectin is important for cell adhesion and providing flexibility in plant tissues but also does not dominate in quantity as a structural element of the cell wall. Each of these substances has distinct functions, but cellulose’s unique properties make it invaluable for producing high-quality paper.