SCIENCE8

• digestion - food is broken down into smaller molecules
• ingestion - process of eating
• transport of food - begins when the food is swallowed
• peristalsis - wavelike connection of the muscular walls
• secretion of materials - secretions of the different digestive glands
• digestion of food - one digestive breaks down food into smaller pieces
• absorption - brings the final products of digestion from the small intestine for distribution to all parts of the body
• excretion - process of removing waste products from the body
• what are the main parts of digestive system?

  • mouth
  • gastrointestinal tract
  • accessory organs
• mouth - section where food enters
• mechanical digestion - coordinated action of the teeth and tongue.
• lips - have sensory detectors that can detect texture and temperature
• palate - moouth's upper boundary where food is pushed against when chewing
• tongue - tasting, mixing and swallowing food
• teeth - physically breaks the food down
• pharynx - connects the mouth to the esophagus
• nasopharynx - passage of AIR ONLY
• oropharynx - passed of FOOD and AIR
• laryngopharynx - passed of FOOD ONLY
• epiglottis - cartilaginous tissue that prevents the entry of food and water into the respiratory tract
• esophagus - long muscular tube where food travels from the mouth to the stomach
• sphincters - prevent the backflow of food
• stomach - hollow and curved organ that functions for storage and breakdown
• small intestine - absorption of nutrients
• duodenum - where chyme mixes with enzymes
• jejunum - site of nutrient absorption
• ileum - site of digestion and further absorption
• large intestine - also known as colon. is a site for vitamin and water absorption. it converts chyme into feces
• rectume and anus - former receives and stores undigested food materials
• salivary glands - secrete saliva into the mouth which cleans the teeth, lubricates the food, and allows chemical digestion
• liver - second largest organs. produces bile
• bile - aids in lipid digestion
• gallbladder - stores and holds bile.
• pancreas - yellowish organ that secretes pancreatic juice