Cellulose
The major component of leaves is cellulose, which serves as a rigid and insoluble 
structural element. Cellulose is a linear polymer composed of D-glucopyranose units
connected through carbons 1 and 4. The fully equatorial conformation of β-linked 
glucopyranose residues stabilize the chair structure of the ring and minimize its 
flexibility. Although cellulose carries many hydroxyl groups, it is not water soluble due 
to its high molecular weight.