Anatomy of the Digestive System Organ System Cluster Prepared by: Maria Michaela Valenzuela, PTRP Reference Seeley, R., Stephens, T., and Tate,
P., Anatomy & Physiology. 8th ed. McGraw Hill Company Inc., (2008) Snell, R., Clinical Anatomy by Regions. 8th ed. Lippincott Williams & Wilkins (2008) Regional Division of the
Abdomen Used to facilitate location of the various organs of the abdominal cavity. Organs of the Digestive System
Alimentary tract: Accessory main passage of Organs Teeth food Mouth Pharynx Esophagus
Stomach Intestines Tongue Salivary Glands Liver Pancreas
Histology of the Alimentary Canal Submucosa Mucosa
Connective tissue Innermost Stratified squamous, Secretory function simple columnar
Meissnerscells plexus of nerve cells Absorption Histology of the Alimentary Canal Muscularis Inner layer of circular
smooth muscle Outer layer of longitudinal smooth muscle Myenteric Plexus of nerve cells Motility function
Serosa Outermost Visceral peritoneum Alimentary Tract: Mouth Anteriorly: teeth Posteriorly: fauces (throat)
Laterally: cheeks Superiorly: palate Inferiorly: muscular floor Alimentary Tract: Mouth Divisions Anterior vestibule Posterior oral cavity proper
Accessory Organ: Tongue Muscular structure occupying floor of the oral cavity Attached to the floor by frenulum Intrinsic & extrinsic muscles Accessory Organ: Teeth
32, distributed over dental arches 1 central incisor 1 lateral incisor 1 canine 2 pre molars 3 molars Accessory Organs: Salivary
Glands Parotid Anterior to the ear Sublingual Lie below mucous membrane of the oral cavity floor
Submandibular Inferior border of the posterior half of the mandible Alimentary Tract: Pharynx Nasopharynx Oropharynx
Laryngopharynx Transmit food Stratified squamous epthelium Alimentary Tract: Esophagus
Extends between the pharynx & stomach 25 cm long Mediastinum, posterior to trachea, anterior to vertebrae Sphincters UES LES
Alimentary Tract: Stomach Divisions Fundus Body Pyloric
Greater & Lesser Curvature Sphincters Cardiac Pyloric Alimentary Tract: Stomach Serosa visceral peritoneum
Muscularis Longitudinal Circular Oblique Mucosal layer with rugae Alimentary Tract: Small
Intestine 6 m long Where greatest amount of digestion & absorption take place Divisions Duodenum Jejunum Illeum
Alimentary Tract: Small Intestine Duodenum Short superior part Duodenal papilla (minor & major) for entry of common bile duct Mucosa & submucosa thrown into
folds plica circulares Microvilli Alimentary Tract: Small Intestine Jejunum & Illeum Smaller in diameter Jejunum: Major site of absorption
(with duodenum) Submucosal Lymphatic nodules: Peyers patches Ileocecal junction with ileocecal valve Accessory Organ: Liver Largest organ
1.36 kg upper quadrant against the inferior surface of diaphragm Lobes (L) & Caudate quadrate
Accessory Organ: Gall Bladder Sac-like structure on inferior surface of liver 8cm long, 4cm wide 3 tunics Accessory Organ: Pancreas
Endocrine & Exocrine functions 2 types of cells Acini Islet Parts Head projecting on the duodenum Body projecting towards the spleen
tail Alimentary Tract: Large Intestine From ileocecal junction to anus Divisions
Cecum Colon Rectum Anal canal Alimentary Tract: Large Intestine Cecum
Proximal Attachment of appendix Colon Ascending colon & colic flexure Transverse colon & left colic flexure Descending colon
Alimentary Tract: Large Intestine Colon 3 bands of Longitudinal muscle: teniae coli Outpouching called haustra Fatty tags: appendices epiploicae
Rectum & Anus Muscular tube lined with Simple columnar epithelium Internal & External Anal Spincter Thank You for Listening!
