BP1-enzymes

• protiens that act as a biological catalyst
• the active site is the part of an enzyme where substrate binds
• active site is complementary to shape of substrate
• substrates are held by weak bonds (hydrogen, ionic, hydrophobic)
• lock and key model - substrate fits perfectly into active site
• substrates are held in place by weak interactions with amino acid side chains on the surface of the protein
• induced fit model - substrate changes shape slightly when it enters active site
• specific- only breaks down substrates that fit in their active site
• rate of reaction-increases with temperature until the enzyme denatures (active site changes site)
• practical-mix amalyse with starch, remove few drops every 10s and add iodine, record time taken for no start to be detected
• food tests

  • starch-iodine orange-->black
  • sugars- Benedict's solution blue-->orange
  • protein- blurts reagent blue-->purple
  • lipids(fats) cold ethanol-->cloudy
• lipase-breaks down lipids -->glycerol+fatty acids

  protease-breaks down proteins-->amino acids

  carbohydrates- breaks down carbohydrates-->simple sugars