|Crustacean form a very large group of arthropods, Crustacean physiology includes normal function of crustacean and their parts. They play major role in aquatic ecosystems, and can easily live in all kinds of habitats. Crustaceans exhibit a great variety of forms; the basic crustacean body consists of a number of segments, or somite. Scientific journal is a periodical publication intended to further progress of science, usually by reporting novel research. There are thousands of scientific journals in publication, and many more have been published at various points in the past. Most journals are highly specialized, although some of the oldest journals publish articles and scientific papers across a wide range of scientific fields. Scientific journals contain articles that are peer reviewed, to ensure that articles meet the journal's standards of quality, and scientific validity. The publication of the results of research is an essential part of the scientific method. If they are describing experiments or calculations, they must supply enough details that an independent researcher could repeat the experiment or calculation to verify the results. Each such journal article becomes part of the permanent scientific record.