Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
U5: Pharynx/Esoph
Digestive System Part III: Pharynx, Esophagus, Stomach
| Question | Answer |
|---|---|
| Pharynx | consists or nasopharynx, oropharynx, laryngopharynx; however, nasopharynx solely part of respiratory tract; does not process food in any way, just passes it to esophagus |
| Oropharynx | lined w/ stratified squamous epithelium for protection against abrasive food; receives food and fluid from oral cavity & air from nasopharynx; passageway for both digestive and respiratory tracts; palatine tonsils located in lateral aspect of the fauces |
| Laryngopharynx | lined w/ stratified squamous epithelium for protection against abrasive food; receives fluid, food, air from oropharynx, so passageway for both digestive and respiratory tracts; esophagus begins at inferior border, from which it receives food and fluid |
| Pharyngeal constrictor muscles | encircle pharynx and function to squeeze bolus into esophagus during swallowing |
| Esophagus | about 10” long muscular tube; extends from laryngopharynx, through posterior mediastinum, into abdominal cavity through opening in diaphragm (esophageal hiatus) and empties into stomach via cardiac orifice |
| Cardiac orifice | esophagus opening into stomach |
| Cardiac/gastroesophageal sphincter | scanty, weak ring of smooth muscle at junction of esophagus and stomach; helps prevent backflow of acidic gastric juice into esophagus |
| Hiatal hernia | condition in which small portion superior aspect of stomach pushes thru enlarged esophageal hiatus, following a weakening of diaphragmatic muscle fibers around edge of hiatus; little bit of stomach is above level of diaphragm & actually in thoracic cavity |
| Heartburn | pain due to regurgitated acidic stomach juice irritating the esophageal mucosa |
| Gastroesophageal reflux disease (GERD) | hiatal hernia and persistant regurgitation of gastric juice and heartburn are associated w/ this condition |
| Stratified squamous epithelium | tissue lining esophagus |
| Skeletal muscle in superior third, mixture of skeletal and smooth in middle third, smooth muscle in lower third | arrangement of muscularis externa of esophagus |
| Stomach | J-shaped organ; extends from esophagus to duodenum; widest part of alimentary canal; temp. storage tank; churns food into chyme; begins breakdown of food proteins w/ pepsin; absorbs water, alcohol, aspirin; food will remain in this organ for about 4 hours |
| Chyme | thick, soupy mixture of partially digested food produced by activity of stomach |
| Pepsin | stomach enzyme that begins breakdown of food proteins |
| Extends from esophagus to duodenum of small intestine; located in upper left abdominal cavity, directly inferior to diaphragm, anterior to pancreas | location of stomach |
| Cardiac, fundic, body, pyloric | regions of stomach |
| Cardiac region of stomach (cardia) | portion of stomach to which esophagus is attached |
| Fundic region of stomach (fundus) | dome-shaped, highest region of stomach, tucked under diaphragm |
| Body of stomach | middle portion |
| Pyloric region of stomach | funnel-shaped, terminal (distal) region that attaches to duodenum of small intestine; located at junction of organs is pyloric sphincter |
| Pyloric sphincter/valve | located at junction of stomach and duodenum of small intestine; controls entry of chyme into the duodenum |
| Greater curvature of stomach | convex left margin of stomach |
| Lesser curvature of stomach | smaller, concave right margin of stomach |
| Rugae | folds/wrinkles of mucosa of internal surface of empty stomach which flatten as stomach fills; resulting expansion accommodates increasing quantity of food within stomach |
| Mucosa, submucosa, muscularis externa, serosa/visceral peritoneum | four layers of stomach wall |
| Lining epithelium of mucosa | consists of simple columnar epithelium; has many mucus-producing cells for protection of stomach lining from its own harsh gastric juices via millions of tiny gastric glands containing mucus-producing cells, parietal/oxyntic cells, & chief/zymogenic cells |
| Parietal/oxyntic cells | cells in gastric glands of mucosa; produce stomach’s hydrochloric acid (HCl) and instrinsic factor. |
| Gastric intrinsic factor | produced by parietal/oxyntic cells; needed for absorption of vitamin B12 by small intestine, which is needed for RBC production |
| Chief/zymogenic cells | cells in gastric glands of mucosa; make and secrete pepsinogen, which is activated to pepsin when it encounters stomach’s hydrochloric acid |
| Enteroendocrine cells | group of cells in stomach and small intestine lining epithelium that secrete hormones that affect digestive activity |
| Circular, longitudinal, oblique | three layers of smooth muscle instead of usual 2; third layer gives stomach greater churning/mixing power |
| Peptic ulcers | crater-like erosions of mucosa of stomach/duodenum/esophagus; most occur in duodenum & stomach; vast majority are usually caused by acid-resistant helicobacter pylori which primarily inhabits stomach; can usually be cured by antibiotics |
| Helicobacter pylori | acid-resistant bacterium that binds specifically to gastric epithelium and induces over-secretion of hydrochloric acid and inflammation that leads to formation of ulcers |
Created by:
mbtrimm
Popular Biology sets