Amylose, Amylopectin, Cellulose, and Glycogen are all polysaccharides: compounds containing many sugars linked together into large molecules. They are formed by glycosidic bonds (which are analogous to peptide bonds which join amino acids to form proteins).
The primary functions of Amylose, Amylopectin, Cellulose and Glycogen are energy storage and food reserve. One example of this is Starch which is %10-20 amylose and %80-90 amylopectin. Starch is the main energy store for green plants and starch is the most important carbohydrate that humans eat.
Cellulose is the main component in cell walls which gives plants their structure.
Glycogen is the main polysaccharide in animals that's used for energy storage.
Amylose, amylopectin, cellulose, and glycogen are polysaccharides. Amylose, amylopectin are storage polysaccharides whereas cellulose and glycogen are structural polysaccharides.
Amylose and amylopectin: are found in plant as starch.Amylose starch is less readily digested than amylopectin. However, it takes up less space so is preferred for storage in plants.
Cellulose: cellulose is a common carbohydrate found in plants which allows the plant to stand upright by forming the basic structure of its cell wall through the process of photosynthesis. It is made up of oxygen, hydrogen and carbon as well as a derivation of glucose.
Glycogen: It is made primarily by the liver and the muscle, but can also be made by glycogenesis within the brain and stomach.