ANATOMY - DIGESTIVE SYSTEM SUMMARY.

1. Defecation - The elimination of indigestible substances from the body as feces. 2. Accessory Digestive Organs - Salivary Glands Teeth Tongue Gallbladder Liver Pancreas 3. Length of GI tract - 30 feet 4. Tissu ...

1. Defecation - The elimination of indigestible substances from the body as feces. 2. Accessory Digestive Organs - Salivary Glands Teeth Tongue Gallbladder Liver Pancreas 3. Length of GI tract - 30 feet 4. Tissue Layers of Walls of the GI Tract - Mucosa Submucosa Muscularis Externa Serosa 5. Mucosa - The inner most layer of the gastrointestinal tract wall. 6. Submucosa - A layer of connective tissue containing major blood and lymphatic vessels and nerve fibers that stimulate the digestive tract. 7. Muscularis Externa - Consists of two layers of smooth muscle, an inner circular layers and an outter longitudinal layer along the digestive tract. Responsible for peristalsis and segmentation. Consists of skeletal muscle in the mouth and upper sophagus. 8. Serosa - The visceral peritoneum. The outermost layer of the intraperitoneal organs of the alimentary canal. 9. Mouth -Food enters the alimentary canal thourgh this, where it is chewed, manipulated by the tongue, and moistened with saliva. 10. Salivary Amylase - An enzyme found in saliva that begins the process of digesting starch as food enters the mouth and is engulfed in saliva. Breaks down carbohydrates into double sugars. 11. Tongue - A skeletal muscle on the floor of the mouth that manipulates food for chewing, tasting, and swallowing. 12. Bolus - A term used to describe food after it has been chewed and mixed with saliva. 13. Lingual Frenulum - Fold of mucous membrane that connects the tongue to the floor of the mouth. 14. Deciduous Teeth - The 20 teeth that begin to erupt around the age of 6 months. Eventually pushed out by the permanent teeth.