The Gastrointestinal System Flashcards
what is Chyme?
pulpy acidic fluid which passes from stomach to small intestine, consisting of gastric juices and partly digester food.
what structures make up the mucosa (inner layer)?
- lamina propria - loose layer of connective tissue containing capillaries
- muscularis mucosae - smooth muscle layer of mucosa
- epithelium - single layer of specialised cells that line the lumen of the GI tract.
The submucosa is …
the midlayer of the GI tube
loose collagenous connective tissue
what is the function of the Muscularis externa?
- motility, getting food from one end to the other
* contains plexus (messiner’s and auerbach’s) -contains neurons.
the Enteric nervous system controls…
Motility, secretion and absorption
located only in the GI tract
what is the Serosa?
outermost layer of the GI tube
- enveloping layer of connective tissue
- covered with a layer of squamous epithelia cells
Exam Question
.
The BLANK forms the outer wall of the GI tract l. the inner layer of the GI tract is called the BLANK and consists of an epithelial layer and an underlying layer of connective tissue called BLANK
Serosa
Mucosa
Lamina Propria
which cells are responsible for HCO3- secretion?
superficial epithelial cells
which cells are responsible for mucous secretion?
mucous neck cells
which cells are responsible for repair?
stem/ regenerative cells
which cells are responsible for HCL secretion?
parietal cells
which cells are responsible for Pepsinogen secretion?
Chief cells
which cells are responsible for hormone secretion?
endocrine cells
- D cells- Somatostatin
- G cells- gastrin
- enterochromaffin like cells - histamine
what are the 4 main functions of the stomach?
1) digestion
2) secretion
3) defence
4) motility
what is Pepsinogen?
- an inactive format of the enzyme Zymogen
Pepsin is the active form
