http://ases.too.lt/forum/pyloric-sphincter&page=2 source: http://www.onemedicine.tuskegee.edu/DigestiveSystem/Stomach/Porcine_Interior.html Rugae is a term used in anatomy that refers to a series of ridges produced by folding of the wall of an organ . Most commonly the term is applied to the internal surface of the stomach ( gastric rugae ). source: http://en.wikipedia.org/wiki/Rugae source: http://apbrwww5.apsu.edu/thompsonj/Anatomy%20&%20Physiology/2020/2020%20Exam%20Reviews/Exam%203/CH23%20Stomach%20Anatomy.htm Email This BlogThis!