Variegated leaves

• Variegated leaves


  • Some parts contain chlorophyll, whilst other parts do not contain chlorophyll
  • Only parts of the leaf with chlorophyll will photosynthesise and test positive for starch
• Testing for starch


  1. Glucose produced in photosynthesis can be stored as starch

  2. Hot water is used to stop any further photosynthesis & remove the waxy cuticle

  3. Ethanol is used to remove chlorophyll - easy to see the change in colour

  4. Test for starch: Iodine
• Positive result for starch test

  Leaves will turn blue black - starch is present, photosynthesis has occurred
• Negative result for starch test


  Leaves will be orange (colour of iodine)