Digestive System ChaPTER 17

Basic Structure Alimentary Canal  Donut Hole 4 Layers: Mouth & Pharynx Esophagus Stomach Small Intestines Duodenum Large Intestines – Colon Accessory Organs Salivary Glands Pancreas Liver & Gall Bladder 4 Layers: Mucosa  Mucus Lubrication & Protection Secretion and Absorption Submucosa Vessels and Nerves Muscularis Peristalsis Circular layer and longitudinal layer Serosa  Serous Fluid

Basic Function Digestion – breakdown of food Mechanical & Chemical Enzymes Absorption – first time food actually enters body/blood stream Villi & Microvilli Excretion – removal of undigestible material Feces formation Add’l function: Vitamin production

Mouth Lips, Cheeks, Gums, Teeth and Tongue Frenulum  tongue “tied” & Frenotomy Gums  Gingivitis Tonsils – Palatine & Pharengeal (Adenoids) 20 Deciduous (Baby) Teeth Incisor, Incisor, Canine, Molar, Molar 32 Permanent (Adult) Teeth Incisor, Incisor, Canine, Biscupid, Bicuspid, Molar, Molar, Molar Wisdom Teeth – 3rd set of molars Impacted Parts of a tooth Crown vs. Root Enamel Cementum, peridontal ligament, alveolar process

Salivary Glands Hard & Soft Palates Salivary Amylase  Starches Parotid largest Submandibular  Gleeking Sublingual  Mucus Hard & Soft Palates Create Bolus Raise Uvula Initiate Swallowing

Pharynx & Esophagus Swallowing Reflex  initiate Peristalsis Epiglottis Closes – directs food to esophagus Esophagus – collapsable tube that connects pharynx to stomach Lots of mucus Esophageal hiatus  hiatal hernia Lower esophageal sphincter Acid reflux