Cellulose mainly αcurs in plants.
Cell wall of plant cells is made up of cellulose. It is a long chain polymer.
In cellulose,
β-D-glucose units are linked by glycosidic linkage between C1 -of one unit of glucose and C4 of another glucose unit.
Thus cellulose contains 1 → 4β glycosidic linkages like those in cellobiose.
