Alimentary System Tissues
Compiled By Muchiri Simon
Edition: 2024/25
, Medical & Nursing | Anatomy I of V pages
1. three key cell types in gi tract with function
modified epithelium = for secretion/ absorption/ protection immune system = 70% of body immune system in
2. features of epithelial lining of gut
secretes mucus for lubrication and protection
secreted hcl, hormones and enzymes for activity of digestive system
absorbs products of digestion
tight junctions form barrier
3. features of gut for protection
highly developed immune system = GALT
diffuse immune cells = lymphocytes, macrophages
organised lymphoid structures = tonsils, appendix
paneth cells in small intestine
acidity of gastric juice
4. features of stem cells
capable of renewing the entire cell population
maintain and renew cells constantly
self renew, proliferate and differentiate
5. 4 layers of the GI tract
mucosasubmucosamuscularisserosa
6. mucosa features
epithelial lininglamina propriasmooth muscle
7. submucosa features
connective tissue with blood and lymph vessels, nerve plexus
8. muscularis features
circular internal layer nerve plexus longitudinal external layer
9. serosa features
connective tissue with mesothelium lining
10. innervation of the gi tract
enteric nervous system
self sufficient but modulated by ANS
11. two plexus and functions
meissners = submucosal (secretory function, mucosal movement, blood flow)
auerbachs = myenteric (between muscle layers, controls peristalsis )
12. epithelium in oesophagus
stratified squamous
Anatomy 2024/25 Edition