Procedures:
1. Remove the label of the two-liter bottle, if there's any.
2. Carefully cut the bottom of the two-liter bottle.
3. The bottle represents the human chest cavity.
4. To hold the two straws in place in the neck of the bottle, use clay or tape.
5. Put one nine-inch balloon at the end of each
straw, and secure them with
rubber bands or tape.
6. The balloons represent the lungs while the straws represent the bronchi.
7. Stretch out the balloon wrap and place it over
the open bottom of the bottle.
Secure it with a rubber band.
8. The balloon wrap represents the diaphragm. You now have a finished model
of the lungs. Now it's time to make the lungs
work!
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