1.3

Cards (24)

  • Food molecules
    large molecules - need to break down smaller to get through gut wall
    insoluble particles - must convert to soluble ones to be transported in blood
  • Food tests
    • starch - iodine solution, brown -> blue / black
    • glucose - benedict's reagent, blue -> any colour
    • protein - biuret solution, blue -> purple , (irritant)
  • Absorption
    transfer of breakdown products into blood
    • small intestine - food
    • large intestine - water
  • Digestion
    breakdown of food, mainly in
    • mouth
    • stomach
    • small intestine
  • Egestion
    removal of any undigested food via rectum and anus
  • The pancreas secretes enzymes that break down carbohydrate, protein and fats.
  • The large intestine absorbs water to form faeces.
  • Digestive system
    A - mouth
    B - oesophagus
    C - liver
    D - gallbladder
    E - pancreas
    F - stomach
    G - large intestine
    H - small intestine
    I - rectum
    J - anus
  • Mouth
    • begins digestion of starch
    • secretes amylase
  • Oesophagus
    • no digestion
    • food is moved down to stomach through peristalsis
  • Liver
    • produces bile
    • bile helps with digestion of fats
  • Gallbladder
    • stores bile
    • releases bile into the small intestine
  • Pancreas
    • produces carbohydrase and lipase
    • these enzymes both act in the small intestine
  • Stomach
    • begins digestion of protein
    • ph of 1-3
    • produces protease
  • Large intestine
    • reabsorbs water that has been added to digestive juices
    • produces faeces
  • Small intestine
    • pancreatic carbohydrase causes breakdown of starch -> maltose
    • protease completes breakdown of protein -> amino acid
    • pancreatic lipase causes breakdown of fats -> fatty acid and glycerol
    • carbohydrase completes breakdown of carbohydrates -> glucose
  • Rectum
    • part of large intestine
    • faeces are stored hwre before egestion
  • Anus
    • faeces are egested from here
  • Peristalsis
    wave of muscular contractions forcing food down the digestive system
  • Carbohydrase
    • breaks down carbohydrates from starch into glucose or simple sugars if starch is not present
    • in mouth, pancreas and small intestine
  • Protease
    • digests proteins into amino acids
    • in stomach and small intestine
  • Lipases
    • breakdown of fat into glycerol and fatty acids
    • in pancreas and small intestine
  • Bile
    • emulsifies fats
    • aids digestion
    • produced in liver
    • stored in gallbladder
  • Enzymes
    • carbohydrase
    • protease
    • lipase
    • amylase