Proteins are found in virtually every living system. They are the enzymes that are the driving force for our biological processes. They are the main components found in hair, skin, tissue and bone, and they provide the active basis for our immune response.Proteins are macromolecules (or polymers) composed of amino acids linked together by covalent peptide bonds.There are 20 different common amino acids, and they can be found in many different combinations (known as sequences) in protein molecules.roteins are found in virtually every living system. They are the enzymes that are the driving force for our biological processes. They are the main components found in hair, skin, tissue and bone, and they provide the active basis for our immune response.