Most commonly, the bachelor's degree is in one of the biological sciences, but not always; in 2005, nearly 40% of medical school matriculates had received bachelor's degrees in fields other than biology or specialized health sciences. All medical school applicants must, however, complete undergraduate courses with labs in biology, general chemistry, organic chemistry, and physics; some medical schools have additional requirements such as biochemistry, calculus, genetics, psychology and English. Many of these courses have prerequisites, so there are other "hidden" course requirements (basic science courses) that are often taken first. Concerns have been raised that these stringent science requirements constrict the applicant pool and deter many potentially talented future physicians, including those from groups historically underrepresented in medicine, from applying.