1. Mouth Structural components Cheeks Lips (labia)
muscle w/ outside layer of skin
inside non-keratinized stratified squamous epithelium
terminate in lips
Lips (labia)
skin outside, mucous membrane inside
connected to gums by labial frenulum
Vestibule - between gums, cheeks

2. Mouth Structural components Oral cavity proper - from gums to fauces
Palates
hard palate - maxillae and palatine bones
soft palate - posterior portion of mouth w/ hanging uvula
Tongue

3. Tongue Forms floor of oral cavity Covered with papillae
skeletal muscle w/ mucous membrane cover
extrinsic muscles
intrinsic muscles
lingual frenulum
Covered with papillae
provide roughness
taste buds

4. Salivary Glands 3 pairs salivary glands Parotid glands
Submandibular glands
Sublingual glands

5. General Histology of GI Tract
Same histological organization from inside to outside and from end to end

6. Mucosa

7. Submucosa

8. Muscularis

9. Serosa

10. Esophagus Muscular collapsible tube located behind trachea
23-25 cm long

11. Peritoneum

12. Peritoneum

13. Stomach Anatomy Cardia Fundus Body Pylorus Pyloric sphincter
Lesser curvature
Greater curvature
Rugae

15. Stomach Mucosa Simple columnar epithelium w/ gastric pits
Gastric glands w/ secretory cells
chief cells
parietal cells
mucous cells
G cells - gastrin
Secretions = 2-3 L l day

16. Pancreas Accessory organ - aids small intestine with food digestion
Anatomy
12.5 cm x 2.5 cm
Connected by 2 ducts to duodenum
Head, body and tail

17. Pancreas Histology - clusters of glandular epithelial cells
1% of cells in pancreatic islets (islets of Langerhans)
endocrine pancreas
glucagon, insulin, somatostatin, pancreatic polypeptide
99% in acini
exocrine portion of pancreas
secrete pancreatic juice

18. Pancreas Secreting cells to small ducts to 2 larger ducts
Larger - pancreatic duct
joins common bile duct from liver, gallbladder
enter duodenum at hepatopancreatic ampulla with common duct
Smaller accessory duct empties into small intestine upstream

19. Liver Liver General Anatomy Heaviest body organ, 3 lbs
2nd largest organ of body
Anatomy
covered in peritoneum
large R lobe, smaller L lobe separated by a ligament

20. Liver

21. Liver Histology Functional unit of liver is lobule, make up lobes
hepatic cells (hepatocytes) in irregular branching plates around central vein
portal artery, vein and lymph vessels around outside of lobule

22. Liver

23. Liver Histology No capillaries
Sinusoids lined w/ stellate reticuloendothelial (Kupffer's) cells
Phagocytize damaged blood cells, bacteria, toxic substances

24. Liver Histology (cont.)
Hepatocytes filter blood and plasma to make bile
Bile from hepatocytes enters bile capillaries (canaliculi)
Canaliculi empty into small bile ducts

25. Liver Histology (cont.)
Small bile ducts  larger right, left hepatic ducts  common hepatic duct

26. Liver Histology (cont.)
Hepatic ducts join cystic duct from gallbladder to form common bile duct
Gallbladder
Common bile, pancreatic duct form hepatopancreatic ampulla
Empty into duodenum

27. Small Intestine

28. Small Intestine Histology highly adapted for digestion and absorption
long, highly convoluted
same 4 layers but modified

29. Small Intestine Histology (cont.) Mucosa villi (fingers) 0.5-1 mm
 surface area
microvilli (brush border)
lamina propria
arteriole
venule
capillary network
lacteal

30. Small Intestine Histology (cont.) Mucosa (cont.)
cavities called intestinal glands
intestinal glands secrete intestinal juice
lined w/ glandular epithelium
goblet cells
enteroendocrine cells
Paneth cells

31. Large Intestine Histology
No villi or permanent circular folds in mucosa
Simple columnar epithelium and goblet cells in long thin intestinal glands
columnar cells with microvilli absorb
goblet cells secrete mucous for lubrication
Solitary lymphatic nodules

32. Large Intestine Histology (cont.) Muscularis mucosa
longitudinal and circular
longitudinal muscles thickened in longitudinal bands (taenia coli) pull lg.int. into haustra (pouches)
Serosa part of visceral peritoneum
Small pouches of peritoneum
filled w/ fat (epiploic apendages) attached to taeniae coli

33. Large Intestine Anatomy (cont.) Rectum Anus
last 20 cm of GI tract, terminal 2-3 cm anal canal
anal columns
Anus
external opening
internal sphincter of smooth muscle (involuntary)
external sphincter of skeletal muscle (voluntary)