W12/L4 Flashcards
What are the 5 main functions of the GIT?
Digestion Absorption Secretion Movement Protection
What is digestion?
The act of breaking complex foods down to small, easily absorbed particles
From the inside out, what are the layers of the GIT?
Mucosa
Submucosa
Muscularis externa
Serosa/adventitia
What are the components of the mucosa?
Epithelium
Lamina propria
Muscularis mucosae
What two forma can the GIT epithelial cells take?
Columnar enterocytes
Stratified squamous
What’s the muscularis mucosae?
A thin layer of SM which forms the boundary of the mucosa
What’s in the submucosa?
Dense, irregular CT
Nerves, small ganglia and blood vessels
Sometimes glands & immune cells
What’s the function of the muscularis externa?
Gut movement
What is the usual makeup of the muscularis externa?
2 layers:
Inner circumferential
Outer longitudinal
Small myenteric ganglia between the layer
What is the histology of serosa?
Fluid-secreting simple squamous epithelium with a thin layer of CT
What epithelium does the oesophagus have?
Non-keratinising squamous epithelium
