The Magnificent Breathing Machine
Return to Chemistry Index
Evangelyn R. Lilly Ray School
5631 S. Kimbark Ave.
Chicago IL 60637
To become aware of the functions of the lungs in our bodies.
To become aware that air is made up of gases.
To become aware that in breathing an exchange of gases takes place in the
1 clear plastic bottle clay or play dough
1 large balloon 1 plastic straw
2 small balloons 2 rubber bands
Explain to the students that they will make a model of their lungs to help
them demonstrate how the lungs and the diaphragm work.
1. Cut the bottom off of the bottle, leaving a portion of the bottom edge
2. Cut the top part of a large balloon and discard. Tie the stem of the
balloon in a knot and slip the open end over the bottom of the bottle.
3. Attach the small balloons to the straw with a rubber band and insert the
straw, balloon-side down into the bottle.
4. Seal the top around the straw with clay or play dough.
5. Let the children experiment by pulling down on the knotted balloon. The
small balloons will inflate the same as when you expand your chest and
inhale air through the nose.
6. After practicing with their models, the class will discuss and conclude:
that breathing is a mechanical process by which there is an interaction
between the organism and the surrounding air; the lungs and other parts
of the respiratory system perform this mechanical process; that we
breathe air (a mixture of gases composed of oxygen, nitrogen, and a
minute amount of carbon dioxide); oxygen, the gas the body needs, comes
from the air; the lungs and other parts of the respiratory system remove
carbon dioxide from the blood as a waste product and that this excess
carbon dioxide is exhaled.
The students must construct the model of the human lungs completely in the
The students will explain each step used to complete their model.
They will name the gases that compose air.
The students will name the gases we exhale.