Proteins

Proteins are biomolecules that contain carbon, hydrogen, oxygen and nitrogen. Proteins are polymers of molecules called amino acids. There are only 20 different amino acids on earth. But, the structure of the amino acids allow them to be joined together in infinite combinations. Therefore proteins can be made of any number of amino acids to create proteins of infinite sizes and shapes. Proteins are the functional portions of living things and are different in each type of organism. They function to control the rate of chemical reactions, regulate cell processes, form structural components like bone, connective tissue, cartilage, keratin and muscle, and transport substances into or out of cell.