digestive 2.0

• GASTROINTESTINAL TRACT


  An organ system which takes in food, digests it, and absorb energy and nutrients, and expels remaining waste as feces. It also also has endocrine functions
• functions


  Ingestion Absorption Digestion Egestion
• Ingestion


  ingest food
• Digestion -

  break down food
• egestion

  get rid of waste
• ORAL CAVITY

  Ingestion and digestion occurs
• digestion

  There is both physical - (due to the teeth chomping food) and chemical digestion - ( salivary amylase)
• ORGANS INVOLVED:


  Teeth, tongue, epiglottis, salivary gland
• Teeth

  grinds food
• Tongue

  pushes food into the esophagus
• Salivary glands

  lubricates
• Epiglottis -

  accessory organ that makes sure that the food doesn’t go to the larynx by covering it while you swallow
• Teeth


  Incisors, canines, pre molars and molars
• l  Incisors -


  biting and tearing
• Canines

  grasping and tearing
• Pre-molars

  • grinding and crushing
• Molars 


  grinding and crushing
• Enamel 


  is harder than dentine
• Dentine 


  is force resistant making it suitable for absorbing long periods of bite forces
• tongue


  a group of muscles
• tongue


  made up of papillae
• tongue


  funjiform, filiform, foliate, vallate
• Fungiform


  - large ones in the front
• Filiform -


  smaller ones in the front
• Foliate -


  large ones in the sides of the back •
• Vallate - 


  very large ones in the back (8 to 10 only)
• l  Papillae -


  helps grip the food and has little vacuums that helps with the grip
• Papillae 


  
  

  Grips food for the taste buds

  • Tastes food
• 5 tastes: 


  bitter, salt, sour, sweet, and umami
• Umami - 


  Dr. Kikumae Ikeda
• Children 


  are picky eaters because they have more taste buds(two times) than the adults
• PHARYNX

  l  Border of the oral cavity
• BOLUS


  l  It is like a slimy ball
• esophagus


  Muscular tube through which food passes from the mouth to the

  stomach
• PERISTALSIS


  mobilizing food throughout the length of GI tract

  Smooth muscle and Involuntary muscle
• Stomach 


  A big muscular pouch which turns the bolus and mixes it with gastric juice, a mixture of stomach acid, mucus, and enzymes.
• acid


  kills bacteria or viruses
• Enzymes -


  break down proteins, lipids
• Mucus - 


  protects the lining of the stomach from the acid
• small intestine


  90% of absorption occurs