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Digestive System (Human): Key Words

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Digestive System (Human): Key Words Digestive System (Human): Key Words Alimentary canal (or Gastrointestinal divided into four lobes. Its many tract or Gut) The digestive tract: a tube functions include the manufacture of bile, starting at the mouth and ending at the a digestive juice. Large intestine anus. Masseter A cheek muscle used to chew. Anus The lower end of the rectum, Mesentery Peritoneum (abdominal forming the outlet of the alimentary membrane) attaching digestive and other canal. It is normally closed by a sphincter. organs to the rear abdominal wall. Appendix (or Vermiform appendix) A Mucous membranes The mucus- short, wormlike tube opening into the secreting linings of the digestive, cecum but closed at the other end. It respiratory, reproductive, and urinary contains lymphoid tissue, which is tracts. involved in immunity. Pancreas A tongue-shaped gland Bile ducts Tiny tubes that carry bile (a located in the abdomen that produces liver secretion) from the liver to the glucagon, insulin, and pancreatic juice. duodenum. Omentum Peritoneum (abdominal Bowel See Large intestine. membrane) linking the stomach to other Buccinator A cheek muscle used in abdominal organs. chewing. Palate The roof of the mouth. Cecum The first part of the large Pancreatic islets (or Islets of intestine, forming a blind pouch. Langerhans) Scattered areas of the Colon The part of the large intestine pancreas that produce glucagon and between the cecum and rectum. It insulin. Liver consists of four sections: the ascending, Parotid glands See Salivary glands. transverse, and descending colons, and Peristalsis Waves of muscular the rectum. contractions that force substances, such Digestion The chemical and mechanical as food, through internal passageways. breakdown of foods into simple Pharynx The throat. substances that can be absorbed by the Pylorus The narrow exit from the body. stomach into the duodenum, closed by a Duodenum The upper part of the small sphincter. intestine, where most chemical digestion Rectum The last part of the colon, where takes place. feces collect before leaving the body. Enzymes Biological catalysts: proteins Salivary glands The lingual, parotid, that speed up chemical reactions without sublingual, and submandibular glands themselves undergoing change. that produce saliva. Epiglottis A cartilage flap behind Sigmoid colon The S-shaped final part the tongue that is closed during of the colon. swallowing to stop food entering the Small intestine The alimentary canal larynx. between the stomach and large intestine, Esophagus (or Gullet) The muscular comprising the duodenum, jejunum, and tube through which food travels between ileum. Most digestion occurs here. the pharynx and the stomach. Sphincter A ring-shaped muscle that Stomach Gallbladder A pear-shaped bag where contracts to close an orifice, such as the bile is stored, below the liver. pyloric sphincter and the anal sphincters. Gastric Relating to the stomach. Stomach A muscular baglike part of the Gastrointestinal tract See Alimentary alimentary canal between the esophagus canal. and small intestine. It stores, churns, and Gullet See Esophagus. partially digests food. Gut See Alimentary canal. Taste buds Tiny sensory organs Haustrum One of the pouches on the (circumvallate papillae, filiform papillae, outer surface of the colon (plural: fungiform papillae) on tongue and palate. haustra). Teeth Bonelike structures in the jaws. Hepatic Relating to the liver. Different types (incisors, canines, Ileum The last part of the small intestine. premolars, molars) are specialized to Jejunum The middle part of the small pierce, tear, crush, and/or grind food. intestine. Tongue A mobile, muscular organ in the Large intestine (or Bowel) The lower mouth, involved in tasting, chewing, part of the alimentary canal, comprising swallowing, and speech. the cecum, colon, and rectum. It absorbs Vermiform appendix See Appendix. water and eliminates body wastes as Villus A minute fingerlike projection. feces. Huge numbers line the small intestine, Liver The largest organ in the body, increasing its surface area (plural: villi). © Diagram Visual Information Ltd..
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