enzymes and digestion

• Digestive enzymes


  Break down big molecules into smaller ones
• Big molecules

  • Starch
  • Proteins
  • Fats
• Small molecules

  • Sugars
  • Amino acids
  • Glycerol
  • Fatty acids
• Digestive enzymes break down

  Big molecules into smaller ones
• Digestive enzymes

  • Amylase
  • Maltase
  • Proteases
  • Lipases
• Amylase

  Converts starch into maltose and maltose into glucose
• Proteases

  Convert proteins into amino acids
• Lipases


  Convert lipids into glycerol and fatty acids
• Bile


  Produced in the liver, stored in the gall bladder, released into the small intestine
• Bile


  • Neutralises stomach acid
  • Emulsifies fats
• Peristalsis


  Muscular contractions that squeeze food through the gut
• Alimentary canal


  • Runs through the body
  • Includes the mouth, oesophagus, stomach, small intestine, large intestine, rectum
• Mouth


  • Salivary glands produce amylase enzyme
  • Teeth break down food
• Oesophagus


  • Muscular tube connecting mouth and stomach
• Stomach


  • Churns food
  • Produces protease enzyme pepsin
  • Produces hydrochloric acid
• Small intestine


  • Produces proteases, amylases, lipases
  • Where nutrients are absorbed
• Villi


  • Increase surface area for absorption in small intestine
• Villi have a thin layer of surface cells and a good blood supply to assist quick absorption