Digestive Flashcards
Ingestion
Taking food into mouth
Secretion
Release of water, acid, buffers, and enzymes into lumen of GI tract
Motility
Churning and movement of food through GI tract
Digestion
Mechanical and chemical breakdown of food
Absorption
Passage of digested products from GI tract into blood and lymph
Defecation
Elimination of feces from GI tract
GI Tract
Tube open from mouth to anus for transit of food.
esophagus, stomach, small intestine, large intestine, and rectum
Accessory Structures
Not part of GI tract, but contribute to food processing.
Accessory structures include the teeth, tongue, salivary glands, liver, gall bladder, and pancreas
Bolus
Chewed food
Chyme
Food in the stomach mixed with stomach acids
Mouth
formed by cheeks, hard & soft palate, and tongue
Tongue
Skeletal muscle, makes floor of oral cavity.
Upper and lateral surfaces have papillae- some tastebuds
Pharynx
Skeletal muscle, moistens and warms air. Consists of nasopharynx, oropharynx, and laryngopharynx
Esophagus
Collapsible, muscular tube. Connects Pharynx to stomach
Stomach
Secrets gastrin into blood, secretes HCl (kills bacteria and denatures proteins, also secretes pepsin.
Parietal Cell
Secrets HCl and intrinsic factor
Chief Cell
Secretes pepsinogen and gastric lipase
Teeth
Adapted for mechanical digestion.
Children=20 teeth named by Letter
Old Children-Adults=32 teeth named by number
Salivary Glands
Parotid
Submandibular
Sublingual
Pancreas
Produces enzymes that digest carbohydrates, proteins, fats, and nucleic acids AND sodium bicarbonate which buffers stomach acid
Liver
makes bile, important in the emulsification of fats
Gallbladder
stores bile until it is needed. Delivers bile via common bile duct
Bilirubin
Catabolized old RBCs from Liver and Gallbladder
Bile Salt Synthesis
Emulsification and absorption of lipids in liver and gallbladder