Jessica Dominguez Rieg, PhD, of the University of South Florida College of Medicine discusses the role of the intestinal epithelium function and dysfunction in diarrheal disease in her talk “Intestinal Epithelial Function.” This lecture was one of four presentations in the 2018 Refresher Course on “GI Physiology: Not Just the Gut Anymore,” presented at the Experimental Biology 2018 meeting and organized by the APS Education Committee. For more information and to listen to other presentations, visit http://www.the-aps.org/refresher.