What happens to carbohydrate molecules inside a cell?

"Comparison of Starch and Cellulose. Both starches and cellulose are carbohydrates which are classified as polysaccharides since they are composed of chains of glucose molecules. While they are similar, starches can be used as energy sources by the human body while cellulose cannot." - hyperphysics. phy-astr. gsu. edu/hbase/Organic/carb. html