Digestive Tract Flashcards
What are the layers of the digestive tract
Mucosa - epi sit on basal lama, lamina propria, muscularis mucosae
Submucosa
Muscularis externa
Serosa
What is the gastro-oes junction
Abrupt transition from stratified squamous epi of oes to columnar epi of Cardia stomach
Some structures of stomach
Oes Fundus Rugae Cardia Body Pylorus Pyloric sphincter
What are gastric pits lined with
Surface mucous cells
What are some other cells of stomach epi p
Parietal
Chief
Enterochromaffin
What doe the chief cell prod
Sec digestive enzymes
What does a parietal cell prod
HCl
What is unusual about muscularis externa
Areas have additional layer
Oblique to usual circular and longitudinal muscle
AIDS churning
Peat is the gastro-duo junction
Abrupt transition from stomach mucosa to duo mucosa
Inner circular layer thickened to make outright sphincter
What are crypts of lieberkuhn
Besides villi
What are plicae circularis and villi
Pc - large fold whic have villi projecting form
Crypts between villi
What is the epi of the tongue
Anterior 2/3 - stratified squamous epi, thin ventral, thick dorsal
Posterior 1/3 - smooth stratified squamous epi
What is the basic structure of the small intestine
Duo
Jej
Ileum
Approx 5 m
What happens at the duo
Receives acidic chyme from stomach which is partly digested
What are brunners glands
Glands in duo submucosa
Stim by presence of acidic chyme and prod a thin alkaline mucous to neutralise chyme
What are enterocytes
Most numerous cells of small intestine epi
Tall Columnar with brush border
Principle absorptive cell
What are goblet cells
Produce mucin to protect epi and lubricate passages of material
What are paneth cells
Found at base of crypts of lieberkuhn
Defensive make lysosomes
What are neuroendocrine cells
Produce hormones that contribute to control of sec and motility in crypts
What are stem cells
Found at base of crots of lieberkuhn they divide and replenish epi
What is galt
Gut associated lymphoid tissue
Scattered lymphocytes
Peyers patches
What are the principle cell types of the large intestine
Absorptive cells - enterocytes - remove slats and water
Goblet cells - sec mucus to lubricate colon
What is teniae coli
3 muscular strips
Outer longitudinal muscle of large intestine
What is the recto anal junction
Distinct junction between mucosa of rectum and stratified squamous epi of anal canal
What is the enteric nervous system
Digestive tract has own nervous system receives input form autonomic nervous system
Coord gut motility
Myenteric plexus especially for motility
Submucosal reg sec