2. A balloon

3. A straw

4. A rubber band(s)May

5. A marker

7. Then, attach the balloon to the bottom of the cut-off bottle with a rubber band.

8. Get a marker, and draw the bronchial tubes on the marker and draw the alveoli, etc.

9. After that, Tape a balloon (without oxygen or helium) to a straw, and then make a hole in the bottle cap, put the straw through the hole, and then tighten the bottle cap.

10. Then, pull the balloon on the bottom and check if it’s secure.

11. If it’s secure, your done with the model.

12. To function the model, then pull the balloon, and the balloon in the bottle should breath in, and when you let go of the balloon, it should breath out.

13. Congratulations! You are now finished with the model of the lungs!!