Cell biology lies at the center of the biological sciences, constituting the bridge between the sub-cellular, molecular levels of organization and the super-cellular, tissue-based and organismal levels. Historically, cell biology has relied upon biochemical and biophysical methods, microscopy, cell manipulation and pharmacological intervention for its progress. However, with the advent of modern techniques in molecular genetics and recombinant DNA technology, cell biology has become more closely allied to the fields of molecular and developmental biology and genetics. Much recent progress in cell biology also derives from discovery of new chemical compounds with effects on cellular processes. Furthermore, cell biology is at the heart of research on cancer, and as the understanding of the cell grows, cell biology has emerged as an important discipline in the biomedical sciences and medicine.