Overview of Gastrointestinal Tract Histology GI Tract Anatomy Radial organization of gastrointestinal tract wall of tubular gastrointestinal tract consists of 4 concentric layers: mucosa login to view 12 more bullets submucosa login to view 4 more bullets muscularis externa login to view 3 more bullets contains myenteric (Auerbach's) nerve plexus in between double layer of smooth muscle contraction causes peristalsis adventitia / serosa login to view 1 more bullet Distinctive Features of Gastrointestinal Tract Histology Esophagus esophageal mucosa non-keratinizing, stratified squamous epithelium muscularis mucosae is a single layer of longitudinally oriented smooth muscle esophageal muscularis externa upper one third of esophagus login to view 1 more bullet middle one third of esophagus login to view 1 more bullet lower one third of esophagus login to view 1 more bullet Stomach gastric mucosa gastric glands occupy gastric mucosa login to view 3 more bullets Small Intestine overview small intestinal mucosa login to view 12 more bullets duodenum duodenal mucosa login to view 3 more bullets duodenal submucosa login to view 4 more bullets jejunum jejunal mucosa login to view 1 more bullet jejunal submucosa login to view 1 more bullet ileum ileal mucosa login to view 8 more bullets ileal submucosa login to view 2 more bullets Large intestine colon colonic mucosa login to view 2 more bullets colonic muscularis externa login to view 1 more bullet anal canal anal canal mucosa login to view 1 more bullet