组织胚胎学课件 七年制英文医学班专用

1. 组织胚胎学课件七年制英文医学班专用 中国医科大学 基础医学院 组胚—英文教学组

2. Chapter 13 Digestive tract

3. ---Digestive system: • Digestive tract • Digestive gland

4. 1. Components of digestive tract ---oral cavity ---pharynx ---esophagus ---stomach ---small intestine ---large intestine

5. 2. General plan of digestive tract ---Except for oral cavity and pharynx, all other organs share a similar histological plan

6. 1) mucosa ---epithelium: • stratified squamous epi.: protecting • simple columnar epi,: digestion and absorption ---lamina propria: LCT-compact CT: contain more cells and fiber • BV, LV-capillaries • Lymphoid T • glands: structures formed by invagination of epi. into lamina propria ---muscularis mucosa: a thin layer of SM

7. 2) submucosa: more dense CT • small artery and vein, LV • glands (esophagus and duodenum) • submucosa N plexus: -multipolar N -unmyelinated NF -function: regulate the contract of SM and secreting of gland *Plica: projection of mucosa and submucosa

8. 3) muscularis externa • smooth muscle • skeletal muscle • inner circular and outer longitudinal *Nerve plexus: regulate the movement of M 4) adventitia: CT • serosa: CT + mesothelium • fibrosa: LCT

9. 3. Esophagus 1)mucosa: • epithelium: stratified squamous epi. • lamina propria: compact CT • muscularis mucosa: longitudinal arranged SM 2)submucosa: • LCT • esophageal gland: mucous gland

10. 3)muscularis: • inner circular and outer longitudinal • upper 1/3: skeletal muscle • middle 1/3: mixed of skeletal M and smooth muscle • lower 1/3: smooth muscle 4) adventitia: fibrosa

11. 4. Stomach ---dilated part ---store food temporarily ---digest protein primarily ---absorb part of water and Ions

12. 1)Mucosa: ---plica-longitudinal ---shallow ditch- gastric area(2-6mm) ---gastric pit- small depressions

13. ①epithelium: simple columnar epi • surface mucous cell: -tall columnar -N ovoid, basally-located -mucinogen granule -tight junction -high HCO3- undissolved mucus • less endocrine cell

14. ②lamina propria: CT contains fibroblast, LC, plasma cell, mast cell and eosinophil, SM • gastric gland(fundic gland)-oxyntic gland • cardiac gland: mucous gland • pyloric gland: mucous gland

15. * Fundic gland -long, branch tube liked gland: /neck, body and basa -five types of cells can be seen

16. a. chief cell or zymogenic cell ---structure: LM: • columnar • Round, basally-located Nucleus • cytoplasm: /basal-basophilic /apical-zymogen granules EM: RER, Golgi apparatus ---function: secret pepsinogen

17. b. parietal cell or oxyntic cell ---structure: LM: • large, pyramidal or spherical • round centrally-located nucleus • eosinophilic cytoplasm EM: • intracellular secretory canaliculus-invaginations • tubulovesicular system • mitochondria

18. ---function: i.secret hydrochloric acid (HCl) -synthesis processes of HCl: in intracellular secretory canaliculus • H+ K+ -ATP pump: get H+ from cell • Cl- channel: get Cl- from blood • H+ +Cl-→HCl(intracellular secretort canaliculi) -function of HCl: • HCl ↓ pepsinogen→pepsin • kill the bacterium

19. ii.secret intrinsic factor- glycoprotein + VB12→absorption of VB12

20. c. mucous neck cell • less, neck part • columnar • flattened, basally-located N • pale stain in HE stain d. stem cell: undifferentiated cell e. endocrine cell • ECL cell: secreting histamine, promote secretion of parietal cell • D cell: secreting somatostatin, inhibit the secretion of parietal cell

21. * cardiac gland and pyloric gland: mucous gland, contain G cell, which secretes gastrin, to promote the secreting of parietal cell * Mucous-HCO3barrier: • 0.25-0.5mm thick mucous • HCl PH: 0.9-1.5 • H+ + HCO3- → H2CO3 →H2O + CO2 ↑ bicarbonatase

22. ③ Muscularis mucosa: inner circular and outer longitudinal arranged SM 2)submucosa: CT with BV, LV, N and fat cell 3)muscularis : thicker • inner oblique • middle circular • outer longitudinal 4) advantitia: serosa

23. 5. Small intestine ---duodenum ---jejunum ---ileum

24. 1)Mucosa ---circular plica ---intestinal villus ---small intestinal gland

25. ①epithelium: ---absorptive cell: • microvilli: striated-border -1-1.4um long, 80nm in D, 2000-3000 -enlarge the surface area to 30 times • cell coat: -0.1-0.5um -enzymes: trypsinogen, amylase - glucose and protein • enzymes-adipose • SER

26. ---goblet cell ---endocrine cell: • I cell: secreting cholecystokinin-pancreozymin • S cell: secreting secretin

27. ②lamina propria: CT (LC, macrophage, plasma cell and eosinophil and mast cell) a. villus: is the projection of epithelium and lamina propria • epithelium: absorptive cell, goblet cell and endocrine cell • lamina propria: CT with central lacteal, fenestrated cap. and SM

28. b. small intestinal gland: is the invagination of epi.into propria • absorptive cell • goblet cell • endocrine cell • stem cell • Peneth cell

29. Peneth cell: LM: -pyramidal, basally- located, in groups -apical: acidophilic G- contain defensin(cryptdin), Lysozyme EM: -protein-secreting cell feature Function: related to immune function

30. ③muscularis mucosa: SM inner circular and outer longitudinal 2)submucosa: CT • Large BV and LV • duodenal gland: mucous gland-secreting epidermal growth factor, promote the epithelial cell proliferation of small intestine

31. 3)muscularis: SM, inner circular and outer longitudinal 4)adventitia: serosa and less fibrosa

32. 6. Large intestine ---absorb water and ions ---structure feature: a.no villus and no circular plica b.well-developed large intestinal gland c.contain more goblet cells d.taeniae coli: longitudinal bunds bag coli