GIT Histology Flashcards
4 layers of the GI tract walls
mucosa, submucosa, muscularis externa, and serosa
Components of the mucosa
Epithelium, lamina propria and muscularis mucosa
What type epithelium lining is in the GIT for protection
stratified squamous
Where is stratified squamos epithelium found
in the pharynx and esophagus
What type epithelium lining is in the GIT for secretion
Simple columnar
Where is simple columnar epithelium found
Stomach and intestines
Responsible for IgA production, is found in the lamina propria
GALT (gut-associated lymphoid tissue
What is the function of the muscularis mucosa
confers some motility to the
mucosa and facilitates discharge of secretions from glands
Function of the submucosa
houses the larger blood vessels and
mucous-secreting glands
2 layers of the muscularis externa
An inner
circular and an outer longitudinal
Describe the muscualris externa in the upper 1/3 of the esophagus and the lower 1/3
The muscle is striated in the upper third of
the esophagus and smooth elsewhere.
Layer of the epithelium that doubles to form mesentery
Serosa
Location of Auerbach’s plexus
between the 2 muscle layers of the muscularis externa
Plexus that is affected in Hirschsprung disease
Auerbach’s plexus ( deficiency of terminal
ganglion cells in the ganglia that affects digestive tract mobility)
Location of intrinsic innervation in the GIT
within the walls of the GI tract
What makes up the extrinsic innervation of the GIT
parasympathetic
(stimulatory) and sympathetic (inhibitory) axons
Function of sensory fibers accompanying the parasympathetic nerves in the GIT
mediate visceral reflexes and sensations, such as hunger and rectal fullness
Location of Brunners glands
Submucosa od duodenum