Digestive System
Order by
167 terms
Terms | Definitions |
|---|---|
 alementary canal | digestive tract consisting of a tube running between the mouth and the anus |
| salivary glands | three pairs of exocrine glands in the mouth that secrete saliva; the parotid, submandibular, and sublingual glands |
| gallbladder | stores and concentrates the bile produced in the liver |
| liver | produces bile and stores glycogen |
| pancreas | has two functions: endocrine: produces insulin and glucagonenzymes, and exocrine: sodium bicarbonate is produced here. |
| mouth | oral cavity; mechanical digestion (chewing) and chemical digestion of carbs start here. |
| pharynx | the throat; last place food and air mix |
| esophagus | muscular tube that connects the mouth to the stomach |
| stomach | large muscular sac that continues mechanical digestion and starts chemical digestion of proteins |
| small intestine | organ in which most chemical digestion takes place. 20 feet long supported by mesenteric. |
| large intestine | organ that absorbs Vitamins, reabsorption of H2O, storage of waste |
| rectum | lower part of the large intestine where feces are stored |
| ingestion | process of taking in food |
| mechanical processing | physical breakdown of foods |
| chemical digestion | process in which enzymes and other chemicals are used to break foods into their smaller chemical building blocks |
| secretion | process of producing a substance within an organ and discharging it |
| absorption | process by which nutrient molecules pass through the wall of the digestive system into the blood |
| elimination | process of passing undigested material out of the anus |
| defecation | elimination of fecal waste through the anus |
| duodenum | first portion of the small intestine which receives secretions from the gallbladder and pancreas. 10 inches long |
| ileum | last and longest portion of the small intestine where most absorption takes place. 11 feet long |
| jejunum | second portion of the small intestine where most chemical digestion is completed. 8 feet long |
| Peyer's patches | collections of lymphatic tissue found along the length of the small intestine |
| propulsion | movement of food from one organ to the next |
| peristalsis | movement of food through the digestive system |
| segmentation | rhythmic mixing of chyme with digestive enzymes in the small intestine |
| mucosa | innermost layer of digestive tract |
| submucosa | layer superficial to the mucosa which contains blood vessels, lymph vessels, and nerves |
| muscularis externa | bilayer in intestines and trilayer in stomach of made up of smooth muscle which consists of a layer running circularly and another running longitudinally and sometimes obliquely. |
| serosa (adventitia) | outer layer the alimentary canal; secretes a watery fluid to reduce friction |
| visceral peritoneum | serous membrane that covers abdominal organs |
| parietal peritoneum | serous membrane that lines the abdominal cavity |
| mesentaries | connective tissues that anchor small intestines and large intestines to the body wall and provide a pathway for nerves and blood vessels |
| tongue | muscular organ which assists with chewing, swallowing, and taste |
| tonsils | clusters of lymphatic tissue found in the pharynx |
| mastication | chewing |
| haustra | pouches of the large intestine that allow expansion and elongation |
| anus | muscular opening at the end of the rectum |
| cecum | first part of the large intestine where appendix is attached |
| glucagon | pancreatic hormone that raises blood sugar |
| insulin | pancreatic hormone that lowers blood sugar |
| microvilli | extensions of the plasma membrane that increase its surface area |
| villi | projections inside the small intestine that increase the surface area for absorption of nutrients |
| bile | a substance produced by the liver that breaks up fat particles |
| ileocecal valve | sphincter separating the small and large intestine |
| rennin | a milk protein-digesting enzyme found in babies but not adults |
| gastrin | hormone secreted by stomach cells that signal glands in stomach to release gastric juice |
| chyme | acidic, semiliquid mass of partially digested food and gastric juice |
| pepsin | enzyme that begins the breakdown of proteins in the stomach |
| mucus neck cells | produce an acidic mucus in the stomach |
| parietal cells | produce hydrochloric acid which kills bacteria and activates pepsinogen |
| chief cells | secrete pepsinogen, the inactive form of pepsin, in the stomach |
| G cells | secrete an alkaline mucus to protect the lining of the small intestine from stomach acid |
| salivary amylase | enzyme in saliva that begins the breakdown of carbs |
| saliva | contains mucus, enzymes, and water; moistens food |
| deglutition | swallowing |
| soft palate | soft part of the back of the roof of the mouth, closes off nasal cavities when swallowing |
| epiglottis | flap of cartilage that covers the trachea while swallowing |
| pyloric sphincter | circular muscle that controls the movement of chyme from the stomach to the small intestine |
| bolus | chewed up clump of food |
| greater omentum | a saclike mesentery that extends from the greater curvature of the stomach, it covers the contents of the abdomen in an apron-like fashion and then blends with the mesocolon |
| surface epithelium, lamina propria, and muscularis mucosa | 3 layers of the mucosa |
| mucosa, submucosa, muscularis externa, serosa | What are the 4 tunics of the digestive system? |
| nerves, blood vessels, and small glands | What does the submucosa layer contain? |
| myenteric plexus | What are the nerve network that control peristalsis and segmentation? |
| submucosal plexus | What nerve network controls the regulation of secretion from thr glands |
| local mechanisms | prostaglandins, histamines Histamine release in stomach - increa acid secretion |
| neural mechanisms | both of these control the secretion of gastric juice and contraction of smooth muscle in the stomach wall |
| hormonal mechanisms | at least 18 peptide hormones; produced by enteroendocrine cells in digestive tract |
| local, neural, and hormonal | Name the three mechanisms of digestive control? |
| myenteric and submucosal plexuses | What are the neural mechanisms in the digestive system? |
| oral mucosa | lining of the oral cavity |
| labia | lips. |
| orbicularis oris | What muscle forms the lips? |
| highly vascular | Why are the labia red? |
| labial frenula | connection between lips and bone (maxilla and mandible) |
| vestibule of oral cavity | space between lips and teeth |
| buccinator muscle and buccal fat pad | What makes up the cheeks? |
| raphe | a ridge that forms a seam between two parts of the roof of the mouth |
| uvula | a small pendant fleshy lobe at the back of the soft palate |
| tongue | a mobile mass of muscular tissue covered with mucous membrane and located in the oral cavity |
| lingual frenulum | anchors tongue to floor of mouth |
| palatoglossal arch | arch closest to tongue on palate |
| palatopharyngeal arch | arch closest to the pharynx and where the palatine tonsils are located |
| parotid gland | 25% secretion; located on anterior to the ear; secretes amylase |
| submandibular gland | 70% secretion located inferior to the mandible |
| glossopharyngeal nerve (IX) | What cranal nerve controls the parotid salivary gland? |
| hypoglossal nerve (XII) | What cranal nerve controls the muscles of the tongue? |
| sublingual gland | 5% secretion; located inferior to the tongue |
| parotiditis | What is mumps? |
| deciduous teeth | baby teeth |
| permanent teeth | adult teeth |
| clinical crown | The portion of the crown which is visible |
| anatomical crown | part of the tooth covered by enamel |
| clinical and anatomical | What are the two names for the crown? |
| root | the part of a tooth that is embedded in the jaw and serves as support |
| enamel | hard white substance covering the crown of a tooth; hardest material in the body |
| dentin | bone (calcified tissue) surrounding the pulp cavity of a tooth |
| pulp | the soft inner part of a tooth (blood vessels and nervous) |
| pulp cavity | contains blood vessels and nerves within the tooth |
| cementum | Tissue that covers the anatomic root |
| root canal | the passage in the root of a tooth through which its nerve and blood vessels enter the pulp cavity |
| periodontal ligaments | Small ligaments that anchor the root of a tooth in the socket of the jaw. |
| alveoli of the tooth | socket of tooth |
| incisors | 2 per quandrant; sharp teeth at the front of the mouth; used for shredding food |
| canines | 1 per quadrant; used in tearing |
| premolars | 2 per quadrant; used for chewing and grinding of food |
| molars | 3 per quadrant; used for grinding |
| gingivitis | inflammation of the gums (gingiva) |
| gingiva | gums |
| buccal, pharyngeal, esophageal phases | What are the three phases of deglutition? |
| buccal phase | Voluntary phase - The first phase in swallowing, the tongue collects food, presses it against the palate to form a bolus, and pushes it back into the oropharynx. the bolus stimulates the tactile receptors and activates the next phase |
| pharyngeal phase | Involuntary phase - involves the elevation of the larynx, reflection of the epiglottis, and closure of the glottis. |
| esophageal phase | involuntary, bollus reached esophagus, peristalsis begins and the enteric nervous system will take over automatically |
| pharyngeal constrictor muscle, palatopharyngeus and stylopharyngeus, palatal muscles | What are the 4 pharyngeal muscles used in deglutition? |
| skeletal muscle, mixture of skeletal and smooth, and smooth muscle | What are the muscularis externa for the esophagus (from top to bottom of the tube? |
| esophageal hiatus | What is the name of the hole in which the esophagus goes through the diaphragm? |
| esophageal glands | What produces mucous in the esophagus? |
| esophageal sphincter | muscle at the upper or lower end of the esophagus that prevents backflow |
| gastroesophageal sphincter | aka cardiac sphincter; at the inferior end of the esophagus connected to the stomach; relaxes to let food enter the stomach |
| gastroesophageal reflux disease | What does GERD stand for? |
| GERD | upward flow of stomach acid into the esophagus |
| simple columnar epithelium | What is the tissue for the stomach? |
| alkaline mucous | hydrochloric acid doesn't eat through the stomach wall because its protected by a thick layer of this? |
| cardia | region of the stomach where the esophagus enters |
| fundus | uppermost domed portion of the stomach |
| body of stomach | middle of the stomach, distensible, large number of glands |
| pylorus | portion of the stomach that connects to the small intestine |
| pylorus sphincter | "Valve" at the bottom of the stomach that restricts food/acid from "leaking out" to the small intestine |
| rugae | folds in the lining of the stomach |
| longitudinal, circular, and oblique muscles | What types of muscles make up the muscularis externa of the stomach? |
| gastric glands | What produces and secretes gastric juice via the gastric pits? |
| Vitamin B12 | What is the intrinsic factor for absorption in the stomach? |
| HCl | hydrochloric acid |
| intrinsic factor production, HCl is converted into pesinogen and pepsin, denatures proteins, destroys microorganisms, breaks down plant cells and animal connective tissue | What are the functions of the parietal cells? |
| pepsinogen | What do chief cells produce? |
| gastric lipase | from stomach, continues to process of lipid breakdown |
| gastrin | produced by g cells, stimulates parietal cells and chief cells, causes contraction of the muscles. |
| somatostatin | produced by D cells and inhibits gastrin |
| cephalic phase, gastric phase, gastrointestinal phase | What are the three phases of gastric control? |
| cephalic phase | response to sight, smell, taste, or thought of food, prepares the stomach |
| gastric phase | presence of food in stomach, triggered by distension of stomach and pH increase; neural, hormonal and local responses. |
| gastrointestinal phase | begins as chyme enters small intestine; controls chyme's rate of release from the stomach |
| secretin | inhibits parietal and chief cells - inhibits gastric secretions; stimulates pancreas to produce bicarbonate - neutralizes the acid; stimulates liver to produce bile - emulsify fats |
| digestion | breakdown of food substances into simpler forms that can be absorbed and used |
| salivary amylase | Enzyme in saliva that breaks down starch |
| lingual lipase | Enzyme secreted under the tongue which begins chemical digestion of some exogenous lipids. |
| pepsin | Enzyme that breaks down proteins in the stomach |
| absorption | the process of absorbing nutrients into the body after digestion |
| thick layer of mucous, lack of nutrient transport mechanisms, relatively impermeable to H2O, it's not digested | Absorption is limited because of... |
| plicae circularis | What are the folds found in duodenum that increase the surface area? |
| lacteals | specialized lymph capillaries located in the villi that line the walls of the small intestine |
| duodenal glands | those in the submucosa of duodenum that secrete alkaline mucus to help neutralize acidic chyme |
| ileocecal valve | Prevents food from moving back into the small intestine once it has entered the large intestine |
| colon | ascending, transverse, descending, sigmoid |
| taeniae coli | longitudinal bands of external muscle on the colon |
| haustra | saclike outpocketings of the large intestine wall |
| rectum | 15 cm after sigmoid colon |
| internal anal sphincter | at superior end of anal canal, under involuntary control |
| external anal sphincter | voluntary skeletal muscle that controls the expulsion of feces from the anal canal |
| anus | opening through which wastes leave the digestive tract |
| metabolic regulation, hematological regulation, bile production | What are the functions of the liver? |
| right, left, caudate, and quadrate | lobes of liver |
| interlobular septa | separate each lobule |
| falciform ligament | a ligament that attaches part of the liver to the diaphragm and the abdominal wall |
| coronary ligament | Mesentery that extends from liver to the transverse septum |
| hepatocytes | secret and absorb nutrients to adjust circulating levels; a.k.a. liver cells |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.