Molecular biology is the branch of biology that involves study of biological activity at a molecular level. Cellular biology deals with the cell structure and function. Molecular and cellular biology involve cellular structure and function and genetic expression studies. It is a biweekly peer-reviewed scientific journal covering all aspects of molecular and cellular biology. It is published by the American Society for Microbiology and the editor-in-chief is Peter Tontonoz. It was established in 1981. Molecular biologist examine plant, animal or human genetics and the variation and relationships between them. Molecular biologist can work with DNA and RNA from humans, plants, animals and other organisms while using their knowledge of chemistry, physiology, genetics, physics and biology in their work.