You can build your own toilet roll model.
You will need:
- two sheets of card (A4 size)
- either seven of the cardboard tubes from toilet rolls or several kitchen roll tubes
- some pipe cleaners to represent the protein - these look better if you can find coloured ones
- some glue
What you do:
1. Use the two sheets of card for the inner and outer surfaces of the cell membrane.
2. Take measurements from Figures 6 and 11 to mark the position of the a-helices on the A4 card. Mark and carefully cut holes at these points to allow insertion of the toilet rolls.
3. Now glue the toilet rolls between the two sheets of card.
4. Join sufficient pipe cleaners together to represent the protein chain and weave this to and fro through the toilet rolls (use Figures 6 and 11 to guide you). You might try to put helical sections inside the toilet rolls.