The answer to this query is that the 20 amino can be combined and/or arranged in a particular order in a million different ways to form different proteins.
Protein molecules are often quite large and are made up of hundreds to thousands of amino acids. The human body has about 100,000 different types of proteins.
There are hundreds of different amino acids and out of these 20 are essential for the body. It is from these 20 that the proteins of the body are made.
How it is possible to make so many different types of protein is dependent on the fact that it is not only the type of amino acids in a protein that determine its function, but also the order in which they are placed. In a protein with 1000 amino acids, a single amino acid placed in a different place will change that protein to an entirely different conformation and subsequently an entirely different function.
