Enzymes

• What is the main objective of the practical investigation?

  Investigating the effect of temperature on amylase
• What apparatus is required for the enzyme investigation?

  • Test tubes
  • Test tube rack
  • Water baths
  • Spotting tiles
  • Measuring cylinder or syringe
  • Glass rods
  • Stopwatch
  • Starch solution
  • Amylase solution
  • Iodine solution
  • Thermometers
• Why is it necessary to set up water baths at different temperatures?

  To test the effect of temperature on amylase
• How much starch solution should be measured for each test tube?

  5 cm3
• What is the temperature range suggested for the water baths?

  From cold to above 50 °C
• What is the purpose of using a thermometer in the experiment?

  To check the temperature of the test tubes
• What should be done when the contents of the test tubes reach the required temperature?

  Pour amylase into starch and mix
• What indicates that starch has been broken down in the experiment?

  The iodine solution no longer turns black
• What are the practical variables in the enzyme investigation?

  • Independent variable: Temperature of amylase
  • Dependent variable: Rate of starch breakdown
  • Control variables:
  • pH
  • Same volume and concentration of starch
  • Same volume and concentration of amylase