Enzymes

• Enzymes


  Biological catalysts which speed up reactions
• Enzymes


  • They are specific for their substrate
  • They are denatured at extremes of temperature and pH
• Lock and key hypothesis


  Models how enzymes and their substrates interact
• Enzymes are folded into complex 3D shapes that allow smaller molecules to fit into them
• Active site


  The part of the enzyme to which a specific substrate can attach or fit on to
• Lock and key hypothesis

  The shape of the active site matches the shape of its substrate molecules, making enzymes highly specific
• Enzyme catalysis


  1. Enzyme splits one substrate molecule into two smaller ones

  2. Other enzymes join smaller substrate molecules together into larger ones
• Denaturing enzymes


  If enzymes are exposed to extremes of pH or high temperatures, the shape of their active site may change, causing the substrate to no longer fit
• It is important to use 'denatured' and not 'killed' as enzymes have never been alive