Search results for: Alejandro suffers from gastroesophageal reflux disease (GERD), also known as heartburn , where stomach contents regurgitate into the esophagus. His physician uses an endoscope to examine his esophagus, and notes that the epithelium lining his lower esophagus has transformed from a nonkeratinized stratified squamous epithelium to a simple columnar epithelium (an epithelium seen in the stomach). What term describes this tissue modification, and why do you think Alejandro’s epithelium changed