Skeleton Notes for Digestion System

• Mechanical Digestion - Physically prepares food for chemical digestion by breaking it up and moving it around
• Chemical Digestion - Enzymes break down food molecules
• Pharynx - Throat
• Epiglottis - flap that covers opening to trachea when swallowing
• Esophagus - tube that carries food from the pharynx to the stomach
• Peristalsis - wavelike contractions that push food toward stomach
• Heartburn - painful burning in the esophagus
• Heartburn happens due to esophagus not tightening as it should, and acid backing up into the esophagus
• Heartburn happening often means you are unhealthy
• It feels like your heart is burning because the nerve runs behind the heart
• Mechanical Digestion in Stomach - peristaltic mixing waves
• Chemical Digestion in Stomach - hydrochloric acid (HCI) creates acidic environment and activates the enzyme pepsinogen into pepsin
• Hydrochloric Acid (HCI)
• Mucus protects the stomach lining from HCI
• Chyme - secretions combine with food to create Chyme
• Peptic Ulcers - open sore in lining of the stomach, small intestine, and esophagus
• Mechanical Digestion in Small Intestine- peristalsis and bile
• Chemical Digestion in Small Intestine - villi
• Pancreatic and intestinal increase the surface area for absorbing nutrients
• Villis - network of capillaries and lymphatic vessels
• Pancreas - keeps blood levels appropriate, sodium bicarbonate releases