Biology

06. Investigation into the permeability of cell membranes using beetroot

  • 00:44 Where is the betalain pigment stored in the cells?
  • 00:55 What happens to the colorimeter absorbance as more betalain is released?
  • 01:07 What is the relationship between temperature and degree of betalain released?
  • 01:13 What must happen to the membrane structure for the betalain to be released?
  • 01:23 Which type of molecule in the membrane structure is the most likely to be damaged by increasing temperatures?

  • beetroot cylinders

  • white tile

  • 5 test tubes

  • scalpel

  • deionised water

  • ruler (mm)

  • 5cm3 syringe

  • 250cm3 beaker

  • forceps

  • water baths set up at 25, 35, 45, 55, 65oC

  • thermometer

  • stop clock

  • colorimeter with a blue/green filter (530nm) or a colour chart

  • white card

  • test tube rack

Hazard Risk Control measure

Scalpel

Cuts to skin

Cut down and away from body onto a white tile or chopping board