Cellulose is a complex carbohydrate, or polysaccharide, that is composed of glucose units and forms the main component of plant cell walls.
A carbohydrate (e.g., starch, cellulose, or glycogen) whose molecules consist of numerous sugar molecules bonded together.
A simple sugar that is an important energy source in living organisms and is a component of many carbohydrates.
A rigid layer lying outside the plasma membrane of the cells of plants, fungi, and bacteria. In the algae and higher plants it consists mainly of cellulose.