Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Introduction to the Gastrointestinal SystemChapter 56
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins GI System (cont.)•The GI system is the only system in the body open to the external environment•Composed of one continuous tube –Begins at the mouth–Progresses through the esophagus, stomach, and small and large intestines–Ends at the anus•Accessory Organs–Pancreas–Liver –Gallbladder
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins GI System
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Layers of the GI Tube•Mucosa•Muscularis Mucosa •Nerve Plexus•Adventitia
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Layers of Nerves in the Nerve Plexus•Submucosal Layer •Myenteric Layer
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Layers of the Gastrointestinal Tract
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Major Activities of the GI System•Secretion: Of enzymes, acid, bicarbonate, and mucus•Absorption: Of water and almost all of the essential nutrients needed by the body•Digestion: Of food into usable and absorbable component•Motility: Movement of food and secretions through the system
