Food, water, sleep, and oxygen. These are essential things for life.
Today, we’re going to take a look at the science behind how breathing works with an easy science experiment!
Materials:
3 balloons, 2 straws, plastic water bottle, scissors, tape
Time Estimated:
15-20 minutes
Directions:
Cut the necks off of two balloons and cut one of the straws in half.
Attach one of the cut balloons to each straw half, then seal with tape.
Make a 2” cut at the bottom of the remaining straw.
Tape one “lung” on either side of the two way split straw.
Cut off the bottom of the water bottle.
Make a hole in the cap.
Place your “lungs” in the bottle and place the cap on the end of the straw, then screw it on.
Cut the neck off of the last balloon and stretch it over the bottom of the bottle.
Pull on the bottle to simulate how real lungs work.
Think Like a Scientist:
What might the plastic bottle and straws represent?
What does the balloon at the bottom of the bottle represent?
How does the balloon at the bottom affect the other balloons or “lungs”?
What process does this model simulate?
How It Works:
The plastic bottle represents our chest and the straws represent our trachea. The trachea is kind of like a breathing tube that connects air from the outside world to our body and lungs. The balloons inside the bottle represent our lungs, and the balloon at the bottom of the bottle represents our diaphragm. As we can see with our model, when the diaphragm muscle stretches downward, air can move into the lungs. When we exhale, the diaphragm relaxes, returning to its original domed shape.
This models the process of respiration, or breathing. The diaphragm moving downward and oxygen coming into the lungs involves the scientific concept of air pressure. Air pressure is a measurement of how much air molecules push on everything around them.
In our lung model, we can see air moving in when we pull on the “diaphragm”. The reason for this is because when we move the diaphragm down, we increase the volume (amount of space) in our chest area. This extra space allows air to rush in because there is more room for the air molecules to move around. So, having more space or volume decreases the air pressure! Because the pressure of the outside environment and the air inside our chest area are so different when we have this extra space, more air is able to move to the lungs.
Looking for more fun at home STEM activities for your young scientist? Check out our workbook full of exciting science experiments and empowering activities!
