Structure of the Intestine Small 320×285 Medium 640×570 Large 1024×913 Download Tiff Original 2400×2139 | (1.4 MB) Description Diagram to show the structure of the small and large intestine and duodenum. Keywords duodenum, intestine Galleries Human Digestive System Source: Cunningham, D.J. Textbook of Anatomy (New York, NY: William Wood and Co., 1903)