More than 200 peptides have been shown to be essential to the proper functioning of the human body. Hormones and enkephalins are among the peptides for which functions have been identified. Characteristics of Proteins. Proteins are large polymers of amino acids. Acidic and basic properties of proteins are determined by the acidic or basic character of the R groups of the amino acids comprising the protein.
Proteins perform numerous important functions in the body.
Proteins are classified structurally as fibrous or globular. They are classified on the basis of composition as simple or conjugated. The Primary Structure of Proteins. The primary structure of a protein is the sequence of amino acids in the polymeric chain. This gives all proteins an identical backbone of carbon and nitrogen atoms held together by peptide linkages.