Monosaccharides are the simplest carbohydrates. Although glucose and fructose have the same molecular formula they have different structures. They cannot be further hydrolyzed to simple sugars. Disaccharides contains two monosaccharides. For example, lactose and sucrose. Polysaccharides on the other hand contains a large number of saccharides. An example is starch, glycogen and dextrans. Amino acids contains an amino acid, carboxyl group and an R-group. Whatever the diagram you have, you just look at the structures contained.