amino acid anal canal anal columns anal sinuses anal valves angular incisure anus ascending colon boston university carbon dioxide cardia cardiac glands cecum cholesterol circular folds descending colon desmosome digestion duodenojejunal flexure duodenum emedicine enzyme epiploic appendix esophagus fundic glands gastric pits gastrointestinal tract glycocalyx greater curvature of the stomach gut-associated lymphoid tissue haustra hepatic flexure houston valve human anatomy ileocecal valve ileum intestine jejunum lacteal large intestine latin lesser curvature of the stomach lymph major duodenal papilla microfilament microvillus minor duodenal papilla nasopharynx nutrient oropharynx parking lot pectinate line pharynx pyloric antrum pyloric canal pyloric glands pylorus rectal ampulla rectum rugae sigmoid colon small intestine sphincter ani externus muscle sphincter ani internus muscle splenic flexure stomach sugar suspensory muscle of the duodenum taenia coli tennis court torso transverse colon upper esophageal sphincter vermiform appendix