lecture 20 - the basic structure of the GI system Flashcards
what is motility in the GI tract
transport of food into and throughout the body, mixing luminal contents and transport waste out
what is secretion in the GI tract
synthesise and release enzymes, mucus and serous fluid into the lumen
what is digestion
break nutrients into smaller pieces
what is absorption
bring nutrients / water from the lumen to internal environment
where would you find stratified squamous epithelium in the gut tube and whats its function
- mouth
- esophogas
- pharynx
- anus
provides protection from abrasion
where would you find simple columnar epithelium in the gut tube and whats its function
- stomach
- small intestine
- large intestine
secretion and absorption
what are the unicellular glands in the GI tract
goblet cells
- columnar
-apical mucus granuelles
what are the multicellular glands in the GI tract (two types)
simple and compound
what is a simple multicellular gland
gland with a single duct (e.g stomach or small intestine)
what is a compound multicellular gland
gland with two or more ducts (salivary glands)
what are the 4 layers to the GI tract
- mucosa
- submucosa
- muscularis
- adventitia
whats the structure of the mucosa in the GI tract
- epithelia attached via basement membrane to lamina propria
- also contains muscularis mucosae
- lymphatics + blood vessels can be found in the lamina propria
what is the submucosa in the GI tract and what does it consist of
below the mucosa
- FCT
- blood vessels
- glands
- submucosal plexus
what is the submucosal plexus
network of nervous tissue that regulates secretion (part of the enteric nervous system)
what are the two layers of muscle in the muscularis in the GI tract
- inner circular
- outer longitudinal
