Digestive tract LIU YING Department of Histology Embryology
Digestive tract LIU YING Department of Histology & Embryology
Tongue Oral cavity Parotid gland- Salivary Sublingual gland Pharynx glands Submandibular gland- Cardiac orifice Esophagus Liver Ascending portion of Pyloric large intestine sphincter Gall- nleum bladder of small intestine Pancreas Small intestine Duodenum of ppendix small intestine -Large intestine Cecum Rectum- Anus
1.Organization of digestive tract *a long tube extending from the mouth to the anus, its main function: -digestion:physical/chemical -absorption two major sections -the oral cavity including oropharynx -the tubular digestive tract
1.Organization of digestive tract * a long tube extending from the mouth to the anus, . * its main function: -digestion: physical/chemical -absorption * two major sections -the oral cavity including oropharynx -the tubular digestive tract
general structure oftubular digestive tract basically four layers 1.Mucosa 2.Submucosa 3.Muscularis 4.adventitia
general structure of tubular digestive tract basically four layers 1.Mucosa 2.Submucosa 3.Muscularis 4.adventitia 1 2 3
Mucosa Epithel stratified mucosa Epith. 2.Lamina proria Lamina propria a layer of L.C.T. Muscularis mucosa macrophage,lymphoid cells (1 gland capillaries 3.Muscularis mucosa inner circular outer longitudinal layer of smooth muscle cells
Mucosa (tunica mucosa) 1. Epithelium -two types stratified squamous & simple columnar epith. mucosa Epith. Lamina propria Muscularis mucosa 2. Lamina propria a layer of L.C.T. macrophage, lymphoid cells (IgA) gland capillaries 3. Muscularis mucosa inner circular / outer longitudinal layer of smooth muscle cells
lumen lumen sIgA antigen w'wiwTw ￥absorptive cell dimer gG lamina propria 毛细淋巴管 mphocyte lymphocyte之 plasma cells lymphoid nodule capilary recyle
Submucosa *C.T.with small blood /lymphatic vessels; *glands only in the esophagus and duodenum *submucosal plexus *also contain lymphatic tissue
Submucosa *C.T. with small blood / lymphatic vessels; *glands only in the esophagus and duodenum *submucosal plexus *also contain lymphatic tissue
Muscularis *two layers of smooth muscle. inner layer:circular muscle. outer layer:longitudinal muscle. *upper esophagus the anus with striated muscle. *three layers in the stomach *between two layers of muscle are a never plexus
Muscularis *two layers of smooth muscle. inner layer: circular muscle. outer layer: longitudinal muscle. *upper esophagus & the anus with striated muscle. *three layers in the stomach *between two layers of muscle are a never plexus
Circular 000th muscle
Jejunum H&E lumen villi with sim columnar epith Adventitia *the outmost layer formed by C.T.with two forms: fibrosa: C.T.blending with surrounding structure serosa: C.T.mesothelium (simple squamous epith.) longitudinal (outside)and circular(inside)layers of smooth n
Adventitia *the outmost layer formed by C.T. with two forms: fibrosa: C.T. blending with surrounding structure serosa: C.T. + mesothelium (simple squamous epith.)