Alimentary system Respiratory system Urinary system Genital system Part Ⅱ Splanchnology Alimentary system Respiratory system Urinary system Genital system Viscera Male Genital system Female Genital system

But the viscera have some general features. 1.Lacations:within or near the important cavities. 2.Tube: each system has a tube with a opening 3.The main functions of the viscera are fulfill the metabolism and maintain the life of the species. General structures of the viscera Hollow organs Solid organs: Hilum

The reference lines of the thorax and abdomen regions Ⅰ. The common used reference lines of the thorax sternal line midclavicular line parasternal line anterior median line- 腹股沟中点

paravertebral line scapular line posterior median line (midvertebral line)

Ⅱ.The abdominal regions upper right quadrant upper left quadrant lower left quadrant lower right quadrant

9 regions hypochondrium epigastric region subcostal plane flank umbilical region transtubercular plane groin pubic region midclavicular line

Chapter 5 The alimentary system (digestive system) digestive canal digestive glands

Composition Digestive canal Digestive glands Mouth Pharynx Esophagus Stomach Small intestine Large intestine Superior digestive canal Duodenum Jejunum Inferior digestive canal Ileum Digestive glands Major salivary glands Liver Pancreas Function: ingestion, digestion, absorption, egesting

Mouth Pharynx Major salivary glands Esophagus Stomach Liver Pancreas Duodenum Large intestine Jejunum Ileum

Section 1 The Oral Cavity Consists of two parts Oral vestibule : between cheeks and lip and teeth Oral cavity proper: within arch of teeth Oral vestibule leads, by the space behind the molar teeth, into the oral cavity proper Boundaries Anterior and lateral: gum and teeth Posterior: oropharyngeal isthmus Roof: palate Floor: tongue, muscles and mucous membrane

Palate Two parts Hard palate: anterior 2/3, formed by the maxilla and palatine bone Soft palate: posterior 1/3 Uvula Palatoglossal arch Palatopharyngeal arch Oropharyngeal isthmus superiorly formed by the soft palate, both sides of palatoglossal arches, and root of tongue inferiorly.

oropharyngeal isthmus※ ※ hard palate soft palate uvula 软腭 palatoglossal arch palatopharyngeal arch oropharyngeal isthmus※ ※

Teeth General features Two sets: Classification: Deciduous Permanent Incisors Canine Premolars Molars

Deciduous teeth: are 20 in number Ten teeth in each mandibular and maxillary arch Central incisor, lateral incisor, canine, first molar and second molar in each quadrant Upper jaw Ⅰ Ⅱ Ⅲ Ⅳ Ⅴ total 20 Lower jaw in. in. can. mol. mol. Eruption: stars at about 6 mouth of age and continues to beginning of two years Shedding: occurs between 6th and 12th years with replacement by permanent teeth

Permanent teeth (adult): are 32 in number Sixteen in each mandibular and maxillary arch Two incisors, one canine, two premolars, and three molars in each quadrant Upper jaw 1 2 3 4 5 6 7 8 total 32 Lower jaw First permanent molar－ appears at about 6 years Third molars (wisdom teeth)－many erupt at any time after 12 years of age or not at all (impaction).

General description Each tooth consists of 3 parts: Crown Neck Root Dental cavity－contains connective tissue, blood vessels and nerves, and is continuous with the periodontal tissue through the root canal and apical foramen.

The types of the permanent teeth incisors canine premolars molars 1 root of tooth 1-2 roots 2( below) or 3(above) roots

crown of tooth neck of tooth root of tooth root canal Gingivae (gums):oral mucosa that surround the teeth and cover adjacent regions of the alveolar bone.

Calcified tissues Periodontal tissue Dentine－ is a yellowish white tissue, that forms the bulk of tooth. Enamel －is a head, brittle white tissue that covers the crown of the tooth Cement－is an unusual form of bone that covers the root of the tooth Periodontal tissue Periodontal membrane Alveolar bone Gum

Tongue －muscular organ Two parts: divided two parts by v-shaped terminal sulcus Body of tongue －ant 2/3， apex of tongue －free rounded tip Root of tongue － post 1/3 At the apex of terminal sulcus is a small median pit, the foramen cecum of tongue

Lingual mucous membrane Papillae of tongue filiform papillae fungiform papillae foliate papillae contain taste buds vallate papillae Lingual tonsil －masses of submucosal lymphoid tissue on the root of tongue

lingual tonsil terminal sulcus vallate papillae foliate papillae fungiform papillae filiform papillae

Inferior surface of tongue Frenulum of tongue －a midline fold of mucous membrane connecting tongue to floor of mouth Sublingual caruncle －small elevation Sublingual fold

frenulum of tongue sublingual fold sublingual caruncle sublingual gland

Muscles of tongue Intrinsic muscles of tongue Involved in changing shape of tongue Include longitudinal, transverse and vertical muscles of tongue Extrinsic muscles of tongue Genioglossus Arises from mental spine of mandible and inserts into either side of midline of tongue Action: acting together draw tongue forward and downward (depresses and protrudes tongue ); acting along making apex of tongue to opposite side

Intrinsic muscles superior longitudinal muscle inferior longitudinal muscle transverse muscle vertical muscle Extrinsic muscles ※ genioglossus

Major salivary glands Parotid gland superficial part and deep part triangular in shape, lies below and in front of the external acoustic meatus, and partially covers the masseter. Parotid duct: arises front anterior border of gland, runs over the masseter a finger’s breadth below the zygomatic arch to pierce the buccinator and opens into the mouth cavity, opposite the upper second molar tooth

Submandibular gland Sublingual gland Position: lies in submandibular triangle, between anterior and posterior bellies of digastric Duct opens on to sublingual caruncle Sublingual gland Position: situated beneath the mucous membrane of the floor of mouth Ducts Major sublingual duct－opens onto the sublingual caruncle Minor sublingual ducts－open onto the sublingual fold

Section 2 The Pharynx General features A –fibromuscular tube, part of digestive and respiratory systems Extends from base of skull to the inferior border of cricoid cartilage (lower border of C6 level) Three segments

nasopharynx soft palate oropharynx upper margin of the epiglottis laryngopharynx Inferior border of the vertebra C6

Nasopharynx －posterior to nasal cavities Extends from the base of skull to level of soft palate Structures Opening of the pharyngotympanic tube Torus tubarius Pharyngeal recess Pharyngeal tonsil opening of the pharyngotympanic tube pharyngeal tonsil torus tubarius pharyngeal recess palate tonsil Oropharynx －posterior to oral cavity Lies below soft palate, extends to upper border of epiglottis Palate tonsils

Laryngopharynx Structures Piriform fossae －lies on each side of the inlet of larynx. piriform fossa

Section 3 The Esophagus General features － a muscular tuber about 25cm long, connecting the pharynx at level of C6 vertebra, passes through the diaphragm at level of T10 vertebra and after 1~2 cm enters the stomach Division: Cervical part Thoracic part Abdominal part

Four constrictions At its beginning, 15cm from incisors, lies at level of C6, is the narrowest part of the esophagus Where it is crossed by the arch of aorta Where it is crossed by left main bronchus, 25cm from incisors, lies at level of intervertebral disc between T4 and T5. Where it passes through the esophageal hiatus of diaphragm, 40cm from incisors, at level of T10

junction arch of aorta left main bronchus esophageal hiatus

Section 4 The Stomach Position: in the epigastric,umbilical, and left hypochondrium regions.

Shape-J-like shape Four regions Two surface: anterior and posterior Two openings Cardia Pyloric orifice: Pyloric sphincter Four regions Cardia Fundus of stomach Body of stomach Pyloric part: Pyloric antrum and Pyloric canal

Fundus of stomach Cardia Body of stomach Pyloric canal Pyloric antrum Pyloric part

Two curvatures Lesser curvature : short, concave and directed to the right and upward, near its lower part is angular incisure Greater curvature : long, convex and directed to the left and downward, at the junction of left margin of esophagus and greater curvature is cardiac notch

cardiac notch lesser curvature cardiac orifice angular incisure pyloric orifice greater curvature pyloric valve pyloric sphincter

Section 5 The Small Intestine About 6-7m long, Divided into Duodenum Jejunum Ilium Duodenum Jejunum Ilium

Duodenum Four parts Superior part Descending part Inferior part Duodenal cap Superior duodenal flexure Descending part Longitudinal fold of duodenum Major duodenal papilla Minor duodenal papilla Inferior duodenal flexure Inferior part Ascending part duodenojejunal flexure

ampulla (duodenal cap ) circular mucosal folds pylorus superior part superior duodenal flexure ampulla (duodenal cap ) circular mucosal folds

minor duodenal papilla descending part minor duodenal papilla inferior duodenal flexure major duodenal papilla

Suspensory muscle of duodenum (ligament of Treitz), a surgical landmark, descends from the right crus of diaphragm to duodenal termination.

Jejunum and ileum

solitary lymphatic follicles jejunum circular fold aggregated lymphatic follicles ileum

Jejunum and ileum Characteristics Jejunum Ileum Position Upper 2/5 Lower 3/5 Diameter Greater Less Wall Thicker Thin Circular folds Larger, numerous and large villi Fewer，smaller and less abundant villi Vascularity Colour Deeper red Paler pink Lymphatic follicles Solitary Aggregated Fat in mesentery More

Section 6 Large Intestine Approximately 1.5m long, Five parts: Cecum Vermiform appendix Colon Rectum Canal

Large Intestine Features Larger Taeniae coli Haustra of colon Omental appendice

omental appendices taeniae coli haustra of colon

Cecum Blind sac, first part of large intestine, with largest diameter and thinnest wall Lies in right iliac fossa The ilium enters the cecum obliquely, and partially invaginates into it, forming the ileocecal valve－consists of two folds, probably delays flow of ileal contents into large intestine

ileocecal fold ileum ileocecal orifice

Vermiform appendix Blind worm-like tube, 6－8cm long, about 0.5cm in diameter Opens into posteromedial aspect of cecum，about 2 cm below ileoceal orifice The base at the appendix lies at the point of convergence of three colic bands (used as a guide to find the appendix during operation)

taeniae coli mesoappendix appendicular vessels

Surface marking of the base is at the so-called McBurney’s point which is at junction of lateral and middle thirds of line joining right anterior superior iliac spine and umbilicus

Mesentery of vermiform appendix Triangular mesentery－extends from terminal part of ileum to appendix Appendicular a. runs in free margin of the meseoappendix then along wall of appendix Tip variable in position Preileal Pelvic Retrocecal Retroileal Subcecal

Colon Ascending colon Transverse colon right colic flexure Transverse colon left colic flexure Descending colon descends almost vertically from left colic flexure to sigmoid colon at left iliac crest. Sigmoid colon－extends from descending colon to rectum at level of S3.

Rectum Position: within pelvic cavity, extends from S3 to pelvic diaphragm. Curves Sagittal plane Sacral flexure convex backward Perineal flexure convex forward. Coronal plane Upper and lower part－convex to the right. Middle part－convex to the left. Lower part of rectum dilated, to form ampulla of rectum,three transverse folds of rectum

sacral flexure ampulla of rectum perineal flexure anal canal

Anal canal Anal columns －6-11 in number, Anal valves Anal sinuses Anorectal line Pectinate line Above line, of endodermal origin Below line, of ectodermal origin Anal pecten White line (anocutaneous line) Anus Anal sphincters Sphincter ani internus Sphincter ani externus

anal columns anal sinus anal valves sphincter ani internus anal pecten sphincter ani externus pectinate line white line

Comparison between the sites above and below the pectinate line   the site above the pectinate line the site below the pectinate line   epithelium simple cuboidal epithelium stratified squamous epithelium   aterial supply superior and inferior rectal artery anal artery venous return hepatic portal vein internal iliac vein lymph drainage lumbar lymph nodes superficial inguinal lymph nodes innervation visceral nerves somatic nerves

Section 7 The Liver Position Most of liver lies in the right hypochondrum and epigastric region, less part extending into the left hypochondrum.

Shape Two surfaces Divided into right and left areas by falciform lig. Diaphragmatic surface Convex and smooth Divided into right and left areas by falciform lig. Visceral surface

right triangular ligament left triangular ligament falciform ligment ligamentum teres hepatis

Visceral surface －has a H-shaped fissures and grooves Left limb of H Anteriorly: fissure for ligamentum teres hepatis Posteriorly: fissure for ligamentum venosum Right limb of H Anteriorly: fossa for gallbladder Posteriorly: sulcus for vena cava

Cross-bar of H is the porta hepatis: traversed by right and left hepatic ducts, left and right branches of proper hepatic artery and hepatic portal vein, nerves and lymphatic vessels. These structures which are surrounded by connective tissue called hepatic pedicle Four lobes: left, right, quadrate and caudate lobes

Left lobe Right lobe Caudate lobe Quadrate lobe Inferior vena cava fissure for ligamentum venosum Caudate lobe Left lobe Right lobe fissure for ligamentum teres Quadrate lobe ligamentum teres hepatis gallbladder

porta hepatis ※※ portal vein common hepatic duct hepatic artery proper

Inferior border –thin and sharp Notch for ligamentum teres hepatis Notch for gallbladder

The segments of the liver The segmentation of the liver, bases upon the principal divisions of the proper hepatic artery and accompanying hepatic ducts and hepatic portal vein－Glisson system. The hepatic veins, however do not follow the same pattern and vary: their main tributaries tend to run rather intersegmental.

Section 7 Extrahepatic Biliary Apparatus Composition Gallbladder Cystic duct Left and right hepatic ducts Common hepatic duct Bile duct

Gallbladder Position :lies in fossa for gallbladder on visceral surface of liver Four parts Fundus of gallbladder Surface projection: at the junction of right midclavicular line and right costal arch Body of gallbladder Neck of gallbladder Function: receives,stores and concentrates bile

cystic duct neck of gallbladder body of gallbladder fundus of gallbladder

Biliary duct system Right and left hepatic ducts unite outside of liver to form the common hepatic duct Cystic duct joins common hepatic duct to form bile duct

Bile duct and pancreatic duct run obliquely through the wall of the descending part of duodenum where the two ducts usually unite to form the hepatopancreatic ampulla (ampulla of Vater), which rounded by sphincter of hepatopancreatic ampulla (sphincter of Oddi), each has an independent sphincteric mechanism for regulating flow, and opens at the major duodenal papilla

Bile is secreted by the liver cells Right and left hepatic ducts Biliary ductuli Common hepatic duct Cystic duct Gallbladder (store, concentrate) when the fat enters the small intestine, the gallbladder contracts, the sphincter of hepatopancreatic ampulla relax Bile duct Major duodenal papilla

major duodenal papilla right hepatic duct left hepatic duct cystic duct common hepatic duct bile duct pancreatic duct hepatopancreatic ampulla (ampulla of Vater) major duodenal papilla

Triangle of Calot Boundaries: the common hepatic duct on the left, the cystic duct on the right, the liver, superiorily Content: cystic artery

Sect ion 8 The Pancreas Shape and Position A soft yellowish lobulated gland Lies behind the peritoneum on the posterior abdominal wall, roughly at the level of of L1~L2

Five parts Uncinate process Head - Flattened and located in C-shaped curvatune of duodenum Uncinate process Neck－constricted part Body Tail－runs in base of splenorenal ligament to reach hilum of spleen

Pancreatic duct Main Pancreatic duct Accessory pancreatic duct Begins at tail and throughout gland Joins common bile duct before entering descending part of duodenum at major duodenal papilla Accessory pancreatic duct Opens 2cm above main duct at minor duodenal papilla

Pancreas Function The pancreas is both an exocrine and an endocrine gland. The exocrine portion of the gland produces a secretion that contains enzymes that are capable of hydrolyzing proteins, fats, and carbohydrates. The endocrine portion of the gland-the pancreatic islet produces the hormones insulin that play a key role in carbohydrate metabolism.

Highlights Definition of superior and inferior alimentary canal. Structures of the soft palate. Definition of oropharyngeal isthmus. Structures of mucous membrane of tongue. Action of genioglossus. Names, position and openings of salivary glands. Classification of pharynx and structures of the nasopharynx. Constrictions of esophagus. Shape and structures of stomach and duodenum.

Highlights Structures of descending part of duodenum. Position of caecum and vermiform appendix. Characteristic of cecum and colon. Position of ileocecal valve. Shape of rectum. Structures of anal canal. Shape and position of liver. Position and structure of porta hepatis. Boundaries and content of Triangle Calot. Formation of biliary ducts. Position and shape of pancreas.