1、消化与营养消化与营养胃肠道组织学胃肠道组织学1ppt课件Digestion & Nutrition2ppt课件教学目标及基本要求教学目标及基本要求1. 掌握消化管的基本结构。2. 了解口腔粘膜的结构。3. 了解舌的结构和牙的结构。4. 掌握消化管各段的结构特点及功能。5. 了解消化管的免疫功能。6. 了解消化管内分泌功能。 3ppt课件General structure of digestive tract mucosa epithelia lining: (stratified squamous or simple culumnar)lamina propria: LCT(vessel, n
2、erve, gland, LT)muscularis mucosa: thin smooth macular muscularis: inner circular, outer longitudinal (skeletal or smooth muscular) adventitia：thin loose connective tissue (fibrosa or serosa) submucosasubmucosal nerve plexusgland(only in esophagus and duodenum)4ppt课件5ppt课件mucous Lower surface：smooth
3、Dorsal surface：irregularmuscularis：mass of striated skeletal muscularTaste budFiliform papillaeFungiform papillaeCircumvallate papillaeTONGUE6ppt课件Filiform papillaeFungiform papillaeFoliate papillae7ppt课件taste buds8ppt课件epitheliumlamina propriaTunica muscularisFibrosaTunica mucosamuscularis mucosaes
4、tratified squamousTunica submucosa skeletal in upper 1/3rdmixed in middle 1/3rdsmooth in lower 1/3rdESOPHAGUS9ppt课件Tunica submucosa with glandsEpithelium (non keratinized stratified squamous)10ppt课件Junction of esophagus and cardia ESOPHAGUS11ppt课件 mucosa: epithelium, lamina propria, mucularis mucosa
5、e gastric pit, gastric gland muscularis: smooth muscle serosa: mesothelium submucosainner oblique, middle circular, outer longitudinalSTOMACH12ppt课件13ppt课件STOMACH: DivisionsHistology shows corpus & fundus to be the same = “fundic stomach”CorpusPylorusCardiaFundus14ppt课件 surface mucous cellgastric pi
6、t-surface epithelia extent into lamina proprialamina propriaCardiac glandFundic glandPylorus gland15ppt课件Fundic gland ： Chief Parietal cell Mucous neck cell Enteroendocrine cell Gastric stem cell16ppt课件v chief cell：zymogenic cellLocation: predominate in the lower of gastric glandLM: small than parie
7、tal cell, basophilic cytoplasmEM: have the characteristics of a protein synthesizingFunction: secreting pepsinogen which activated in acidic environment into pepsin.17ppt课件v parietal cell ：oxyntic cellLocation: mainly in the upper half of gastric glandLM: round or pyramidal morphology and intensely
8、eosinophilic cytoplasmEM: intracellular canaliculus and abundance of mitochondriaFunction: secreting HCl and intrinsic factor 18ppt课件19ppt课件Mucous neck cells present in cluster or as single cells between parietal cells in the necks of gastric glands.Gastric stem cell few in number, these cells can d
9、ifferentiate into mucous neck, parietal, chief and enteroendocrin cellsSTOMACH: Cell typesChief/Peptic cellEnteroendocrine cell small, pale, few; granules are located basally for release into the lamina propriaparietal cell/oxyntic cell20ppt课件Cardiac regionGland is often coiled and has a large lumen
10、Secrete mucus and lysozyme Junction of esophagus and cardia 21ppt课件Pylorus region Glands have long pits and short coiling Secrete mucus and enzyme lysozymeG cells secret gastrin, D cells secret somatostatin22ppt课件SMALL INTESTINE consist of duodenum, jejunum and ileum the main site of food digestion,
11、 metabolite absorption, and endocretion23ppt课件24ppt课件duodenumjejunumplicae circulares25ppt课件intestinal villiCentral lacteal 26ppt课件Mucous membraneMicrocilli: cylindrical protrusion of the apical cytoplasm and the cell membraneIntestinal villi: out growths of the mucosa (epitheliam plus lamina propri
12、a) into the lumen Plicae circulares: the semilunar or spiral projection of mucosa and submucosaFunction: increasing the area of contact between the intestinal surface and food.27ppt课件striated border(microvilli)absorption cellgoblet cellIntestinal villus28ppt课件Intestine glandAbsorption cell: tall col
13、umnar cells with striated border(microvilli)Goblet cell: less in the duodenum and increase in numbers the ileum is approached. Paneth cell: in the basal portion of the gland, synthesize a complex of protein and polysaccharide Enteroendocrine cell: secret hormoneUndifferentiated cell: gastric stem ce
14、lls 29ppt课件paneth cellpaneth cellgoblet cellgoblet cellabsorption cellabsorption cell30ppt课件Characteristics of different small intestine： Decreased plicae circulares Increased goblet cells in mucous Increased lymphoid tissue in lamina propria and submucous (from duodenum to ileum)31ppt课件duodenum32pp
15、t课件ileum33ppt课件 Consists of rectum, colon and appendix Long intestine glands, no villi Great abundance of goblet and absorptive cells, no Panthe cells The lamina propria is rich in lymphoid cells and nodulesLARGE INTESTINEFunction: absorption of water and formation of the fecal mass plus production
16、of mucus34ppt课件large intestine35ppt课件junction of rectum and anus36ppt课件 an evagination of cecum with small, narrow and irregular lumen abundance lymphoid follicles in its wall fewer and shorter intestinal glands compared with other section of large intestineAPPENDIX37ppt课件appendix38ppt课件constitute d
17、iffused lymphoid cellssolitary lymphoid noduleaggregated lymphoid noduleM cell(microfold cell)lymphoid tissue of the gastrointestinal tract39ppt课件M cellM celllocation: overlaying the lymphoid follicles of Peyers patchesmorphology: numerous membrane invaginations forming pit at their apical and later
18、al surfaces and intraepithelial lymphocytes are contained in itfunction：endocytose antigens and transport them to lymphoid cells, so that initiate immune responses40ppt课件41ppt课件lymphoid tissue of ileum42ppt课件lymphoid tissue of appendix43ppt课件 a serious of widely distributed cells with characteristic
19、s of the diffuse neuroendocrine system open type: cell presents microvilli and contacts the lumen closed type: cell apex is covered by other epithelial cells function: modulate the digestive activity with nervous systemEndocrine cells of the gastrointestinal tract44ppt课件45ppt课件Endocrine cells46ppt课件47ppt课件48ppt课件49ppt课件nerve plexus50ppt课件
