安徽医科大学基础医学院：消化道（讲稿）Digestive tract

Anhui Medical University Chapter 11 Digestive tract Lyu Zhengmei Department of Histology and Embryology, Anhui Medical University

Anhui Medical University Chapter 11 Digestive tract Lyu Zhengmei Department of Histology and Embryology, Anhui Medical University

Anhui Medical University introdction Mouth ◆Digestive tract(DT) Pharynx and Digestive glands Esophagus ===Digestive system: Liver. Stomach ◆Functions of DT: Large Intestine Obtain molecules from Small Intestine ingested food. Appendix- A protective barrier for the Rectum Anus body

Anhui Medical University Digestive tract (DT) and Digestive glands ===Digestive system: Functions of DT: Obtain molecules from ingested food. A protective barrier for the body. introdction

Anhui Medical University Functions Oral cavity Ingestion and Initial fragmentation esophagus Conduct food from oral to stomach Stomach Complete fragmentation and initial digestion Duodenum Get enzymes from pancreas and liver Jejunum and lleum Complete digestion and main absorption 0 Large intestine Absorption of Water and ions Elimination of waste products

Anhui Medical University Functions Oral cavity Ingestion and Initial fragmentation esophagus Conduct food from oral to stomach Stomach Complete fragmentation and initial digestion Duodenum Get enzymes from pancreas and liver Jejunum and Ileum Complete digestion and main absorption Large intestine Absorption of Water and ions Elimination of waste products

Anhui Medical University

Anhui Medical University

Anhui Medical University Part One Oral Cavity and Related structures

Anhui Medical University Part One Oral Cavity and Related structures

Anhui Medical University Oral cavity The oral cavity extend from lips to pharynx. lined by nonkeratinized stratified squamous epi.,except the gum and hard palate(keratinized). The wall of the oral cavity is made up of CT,muscles and bone. Superior lip The oral cavity contains Gingivae(gums) Superior labial frenulum Palatine raphe the lips,the teeth,the Palatoglossal Hard palate- arch tongue and salivary glands. Palato Soft palate pharyngeal arch Uvula Posterior wall Palatine of oropharynx tonsil Tongue Duct of Lingual submandibular frenulum gland Gingivae(gums) Vestibule Inferior labial Inferior lip frenulum

Anhui Medical University  The oral cavity extend from lips to pharynx.  lined by nonkeratinized stratified squamous epi., except the gum and hard palate (keratinized).  The wall of the oral cavity is made up of CT, muscles and bone. Oral cavity  The oral cavity contains the lips, the teeth, the tongue and salivary glands

Anhui Medical University Papillae Foliate ●Filiform papillae ●Fungiform papillae ●Circumvallate papillae a).Filiform papillae:The most numerous.Present over entire surface.small and conical in shape. b).Fungiform papillae:resemble mushrooms,a narrow stalk and a dilated upper part

Anhui Medical University  Filiform papillae  Fungiform papillae  Circumvallate papillae Papillae a). Filiform papillae: The most numerous. Present over entire surface. small and conical in shape. b). Fungiform papillae: resemble mushrooms, a narrow stalk and a dilated upper part. FL Fg Foliate CV

Anhui Medical University c).Circumvallate papillae:The largest papillae. CV is encircled by a deep cleft. The epthelium contains numerous of taste buds. Underlying of the mucosa,there are serous glands Foliate Fg VE:serous glands(von Ebner's)

Anhui Medical University c). Circumvallate papillae: The largest papillae. CV is encircled by a deep cleft.  The epthelium contains numerous of taste buds.  Underlying of the mucosa, there are serous glands FL Fg Foliate CV VE: serous glands(von Ebner’s)

Anhui Medical University Taste bud 10,000 TBs in your mouth,present in the epi.of fungiform papillae,circumvallate papillae,etc. a onion-shaped structure made up of modified epithelial cells. .a small cavity that opens to the surface through a taste pore. Taste pore .The cells in TB are of 3 basic Microvilli types.Receptor cells or taste cells, Supporting cell supporting cells,which have microvilli on the tip of the cells Taste cell and basal cells. Basal cell Afferent nerve fiber

Anhui Medical University Taste bud 10,000 TBs in your mouth, present in the epi. of fungiform papillae, circumvallate papillae, etc.  a onion-shaped structure made up of modified epithelial cells.  a small cavity that opens to the surface through a taste pore.  The cells in TB are of 3 basic types. Receptor cells or taste cells, supporting cells, which have microvilli on the tip of the cells and basal cells

Anhui Medical University The same taste bud can respond to 4 types of taste (sweet,sour,salty and bitter).The sweet and salty is less sensitive,but bitter is most sensitive. epi the

Anhui Medical University  The same taste bud can respond to 4 types of taste (sweet, sour, salty and bitter). The sweet and salty is less sensitive, but bitter is most sensitive