Enzymes

• Catalyst


  A molecule that speeds up chemical reactions, without being used up or changed itself
• Enzyme


  A biological catalyst that speeds up chemical reactions
• Enzyme made up of 


  • Made up of protein
• Substrate


  The substance that an enzyme acts upon
• Investigating the effect of temperature on amylase activity


  1. Label pans and test tubes

  2. Add starch solution to test tube

  3. Add amylase to test tube

  4. Put test tubes in water bath at set temperature for 2 minutes

  5. Use pipette to take sample and test with iodine

  6. Record time until iodine goes yellow
• Denatured enzyme


  An enzyme where some of the bonds holding the shape of the active site have broken, so the substrate can no longer fit
• As temperature increases


  Enzyme activity increases
• As temperature continues to increase past the optimum


  Enzyme activity decreases
• Optimum pH


  The pH where an enzyme works best and catalyses fastest
• At pH above the optimum


  The enzyme has denatured and the shape of the active site is no longer complementary to the substrate
• Enzyme activity decreases when the enzyme has denatured and the shape of the active site is no longer complementary to the substrate