GI tract- Stomach

what are the 4 layers the tube of digestive organs is composed of

mucosa, submucosa, muscularis, serosa

function of stomach

continues mechanical and chemical digestion of the bolus

how many regions is the stomach composed of

4

names of the 4 regions of the stomach

cardia, fundus, body, pylorus

what is the cardia of the stomach

small, narrow, superior entryway into the stomach lumen from the esophagus

what is the cardia orifice

internal opening where the cardia meets the esophagus

what is the fundus

dome shaped region lateral and superior to the esophageal connection with the stomach

what part of the fundus contact the diaphragm

superior surface

what is the body (corpus) of the stomach

largest region of the stomach, inferior to the cardiac region and fundus

what is the pylorus of the stomach

narrow, medially directed, funnel shaped pouch that forms the terminal region of the stomach

what parts is the pylorus divided into

pyloric antrum and pyloric canal

what is the pyloric antrum

more expanded region near the body

what is the pyloric canal

the more narrow region near the duodenum

what is the pyloric orifice

opening into the duodenum of the small intestine

what is the pyloric sphincter

thick ring of circular smooth muscle surrounding the pyloric orifice

what does the pyloric sphincter regulate

entrance of chyme into the small intestine

when does the pyloric sphincter open

upon parasympathetic innervation

when does the pyloric sphincter close

upon sympathetic innervation

what is the greater curvature of the stomach

inferior convex border of the stomach

what is the lesser curvature of the stomach

superior concave border of stomach

internally the stomach lining is composed of what

numerous gastric folds/ rugae

when are gastric folds seen

ONLY when stomach is empty

mucosa is what

mucus membrane, epithelium, loose connective tissue, thin to absent layer of smooth mm

submucosa is what

mucus glands, blood vessels, nerves

muscularis is what

2 layer of smooth m, layer around GI tract and along GI tract

serosa/adventitia is what

intraperitoneal is serosa, retroperitoneal id adventitia

esohpagus is what

not a musce, just made up of muscle layers

stomach has how many layers

3

what is the muscle considered

holding organ

what do gastric pits do

line gastric mucosa

what do gastric glands do

open into gastric pits, secrete acids/ digestive enzymes