The Breathtaking Model of the Lung
Grade: 5
Strand: Understanding Life Systems
Topic: Human Organ Systems
Specific Expectations:
• Demonstrate an understanding of the structure and function of the respiratory
system and the interactions of organs within that system
Materials Needed:
• 1 clear plastic 500mL pop bottle
• Modeling clay or plasticine
• 1 regular latex glove (the kind doctors use)
• 1 small balloon
• 1 plastic straw
• 2 elastics – one small to hold balloon in place and one larger and thinker one to
hold glove in place
Procedure:
1) Cut the bottom off the bottle (This
represents the rib cage).
2) Stretch the latex glove tightly over the
bottom of the bottle and attach with the
large elastic. Create a knot in the glove
by tying all the figures on the glove
together in one knot. (This represents
the diaphragm).
3) Attach the small balloon to one end of
the straw with the small elastic and
insert the straw and balloon into the
bottle so the open straw sticks out of the
neck of the bottle (This represents the
lungs and the trachea).
4) Seal the bottleneck around the straw
with clay.
5) Let the children experiment by pulling
down and pushing up on the glove. The
small balloon should inflate when the
glove is pulled down and deflate when
the glove is pushed up.
6) Have students put their hand over the
top of the straw while pulling and
pushing the glove. (Represents inhaling and exhaling)
Scientific Principle:
The diaphragm is a large dome shaped band of muscle underneath the lungs at the
bottom of the chest cavity. When you inhale, the diaphragm contracts, flattens and moves
downwards allowing oxygen into the lungs. This occurs because as the diaphragm
contracts the volume of the chest cavity increases and the pressure inside decreases. Due
to the lower pressure inside the chest cavity, air will rush in through the nose and mouth
down the trachea and into the lungs to equalize the air pressure on the inside and outside
of the lungs. When you exhale the diaphragm relaxes and moves upwards returning to its
original dome shape forcing the air out of the lungs.
References:
Head to Toe Science By Jim Wiese pg 52 & 53 (ISBN: 0-471-33203-8)
Opportunities and Other considerations:
• If model is not working
o make sure that the clay forms a proper seal around the straw
o make sure that the regular sized balloon covers the bottle opening and
extends up the side of the bottle
o Make sure that the straw is held tight within the small balloon , but is not
pinched shut
• To save time and prevent student injuries consider precutting the bottoms off of
the pop bottles
• Have students pinch the top of the straw and pull on the diaphragm to see if the
lungs will expand. This is the same as if the student where to pinch their nose and
shut their mouth. By blocking the mouth and nose at the same time or pinching
the straw shut it becomes impossible to breath.
• Cool website:
http://www.lungusa.org/site/c.dvLUK9O0E/b.40743/k.753C/Learn_About_Your_
Respiratory_System.htm
• SMART Board: (Interactive model of the respiratory system)
o Open Notebook software 10
o Click on 2nd tab on the left hand side panel with the icon that looks like a
picture frame
o Choose Essentials for educators folder
o Select science and technology folder
o Select biology
o Select Human body
o Click on interactive and multimedia menu
o Drag Breathing and respiration icon to notebook page
Melissa Holland and Nancy Knight