|Protein is the building block of the body made up of amino acids and responsible for most of the complex functions that make life possible. It is the chief class of molecules studied in the biochemistry. It plays major structural and functional roles and enzymes are vital to metabolism. A journal is a periodical publication intended to further progress of science, usually by reporting new research. Most journals are highly specialized, although some of the oldest journals publish articles, reviews, editorials, short communications, letters, and scientific papers across a wide range of scientific fields. Journals contain articles that peer reviewed, in an attempt to ensure that articles meet the journal's standards of quality, and scientific validity. Each such journal article becomes part of the permanent scientific record.