digestive system

• Mouth


  Mechanical breakdown of food

  produce amylase
• Oesophagus


  Muscular contraction
• Stomach

  Muscular walls churn food break down to useful form

  Prodce protease snd hydrochloric acid
• Liver


  Neutralise HCL

  Emulsifies fat

  produce bile (alkaline)
• Gall bladder


  Store excess bile
• Pancreas


  Produce digestive enzymes and release them to small intestine

  produce amylase, protease, lipase
• Small intestine


  Produce digestive enzymes

  food absorbed into blood

  produce amylase, protease, lipase
• Large intestine


  Water absorbed from food
• villi

  • finger-like cell
  • provide larger surface area - fast diffusion
  • one cell thick - short distance for diffusion
  • capillary - maintain concentration gradient for quick diffusion
• starch

  • test with iodine solution
  • orange to blue black
• protein

  • test with biuret's solution
  • turn purple
• sugar (glucose C6H12O6)

  • test with benedict solution
  • blue to brick red
  • water bath
• lipid

  • ethanol
  • turn cloudy/milky
  • shake well