This document describes a model of the respiratory system using balloons and straws. The plastic bottle represents the chest cavity, straws represent bronchi, small balloons represent lungs, and large balloons/cellophane represent the diaphragm. Pulling down the diaphragm balloon causes the lung balloons to expand, representing inhalation. Pushing up the diaphragm balloon causes the lung balloons to contract, representing exhalation. The diaphragm controls air moving in and out of the lungs by changing the chest cavity size and pressure.

1. BOTTLED BALLOONS
Bronchi
Lungs
Chest Cavity
Diaphragm

2. GUIDE QUESTIONS
 What parts of the lungs your model represent?
Plastic bottle- Chest cavity
Straws- Bronchi
Small Balloons- Lungs
Large Balloons/Cellophane- Diaphragm
 What happens as you pull down the balloon?
As the balloon/cellophane is pulled downward , the small balloons
expand. This shows that as we inhale, the diaphragm contracts and
moves downward and air is forced in.
 What happens as you push up the balloon?
The smaller balloons contracts. This means that as we exhale the
diaphragm relaxes and the lungs contract.

3.  How does the movement of the diaphragm cause the air
to go in and out of the lungs?
As we inhale the diaphragm contracts and the chest cavity as
well as the lungs expand. There is now more space and less air
pressure. Now, because of the higher air pressure outside the lungs,
air pushes into the lungs where there is low pressure.
The reverse action happens when we exhale. The diaphragm
relax and the lungs contracts. There is now less space and greater
air pressure inside the lungs. It pushes the air outside where there is
lower pressure.
 What will happen if you prick the balloon?
The balloon represents the diaphragm of the respiratory
system. If it is pricked or somehow damaged, the whole system will
fail, and a person with a damaged diaphragm will eventually die.

4. CONCLUSIONS
 The experiment shows a more definite explanation
about how the lungs work. It also explained the
connection of how the air goes to the lungs and the
air pressures outside and inside the body.
 The diaphragm plays an important role in
respiration, because without it we cannot take in air
that carries oxygen which is necessary for cellular
respiration. And take out carbon dioxide that may
harm us if it is not taken out.