Hands-on Activity: Just Breathe
Educational Standards :
Learning Objectives (Return to Contents)
After this activity, students should be able to:
Materials List (Return to Contents)
Each group needs:
Introduction/Motivation (Return to Contents)
Have you ever been on a crowded subway or bus? You probably could not wait to get out where there were not as many people, and you could move around freely. This is similar to the process that causes air to flow in and out of your lungs. The air molecules are either crowded outside (in the environment) and want to get into the lungs where there are less air molecules (inhalation), or they want to get outside because they are too crowded inside the lungs (exhalation). When you inhale, your diaphragm muscle contracts downward and rib muscles pull upward causing air to fill the lungs. Can you think of why? Well, when your diaphragm moves down and ribs move up, they make more space in your chest (in the thoracic cavity) for air. This also decreases the pressure on your lungs so the air will flow in from the outside. The opposite happens when you breathe out. Your diaphragm relaxes and the ribs and lungs push in which causes air to be pushed out.
Engineers need to understand the respiratory process in order to design machines and medicines to help people whose respiratory systems function improperly or with difficulty. Have you ever known someone who suffers from asthma or pneumonia? Well, chemical engineers design devices and medicines, such as inhalers filled with an adrenergic bronchodilator, to help people breathe better. Engineers have also worked on developing an actual artificial lung that helps patients breathe while fighting off nasty infections. Aerospace engineers design the systems that help astronauts breathe easily during space flight.
Engineers use models to study complicated processes and better understand them. In this activity, you will act like engineers by building a model of the lungs in order to study the breathing process and what happens when you breathe in an out.
Vocabulary/Definitions (Return to Contents)
Procedure (Return to Contents)
Before the Activity
With the Students
Attachments (Return to Contents)
Troubleshooting Tips (Return to Contents)
When cutting off the plastic bottle bottom, make sure that the edges are as smooth as possible so it does not rip theballoon on the bottom. If edges are rough, bind them with masking or duct tape.
Seal any potential leaks with poster tack.
Assessment (Return to Contents)
Discussion Questions: Solicit, integrate and summarize student responses.
Activity Embedded Assessment
Worksheet: Have students record their observations and complete the Lung Worksheet. Review their answers to gauge their mastery of the subject.
Presentation and Informal Discussion: Have one or more groups demonstrate how the lungs work by using their project. Next, hypothesize with the class: What would happen to the respiratory system if we punctured it? Have one group puncture the cavity (bottle) or diaphragm (rubber bottom) and demonstrate what happens to the lungs if this part of the body is damaged. (Answer: The lungs are unable to inflate and/or deflate if there is a leak in the chest cavity. The lungs cannot maintain the pressure difference.) Discuss with the class: What could engineers do to help fix a puncture in someone's lungs?
Activity Extensions (Return to Contents)
Have students research respiratory diseases and how they affect the function of the respiratory system. Can they alter their model to show what happens to the lungs with these diseases? Can they demonstrate on their models what has been done to help people with respiratory problems?
Engineers have developed an artificial lung to help people fight infection. The artificial lung is approximately 18-inches long and consists of membranes that pass oxygen to the blood and remove carbon dioxide. It is inserted through a vein in the leg and lodged in the main vein (the vena cava) passing blood to the heart. The blood is re-oxygenated through a catheter that is attached to an oxygen supply. Have students create a drawing of a machine that could help their model lung "breathe" without having them pull down or push up on the lower balloon. Explain that this is how an engineer might begin to develop life-saving machines.
Activity Scaling (Return to Contents)
For lower grades, have students make one lung rather than two. Use a smaller water bottle rather than a 2-liter bottle and one balloon lung rather than two.
References (Return to Contents)
U.S. Department of Health and Human Services, National Institutes of Health, National Heart, Lung and Blood Institute, Diseases and Conditions Index, "How is Asthma Treated?" Accessed May 23, 2006. http://training.seer.cancer.gov/anatomy/respiratory
U.S. National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program, Training Website, Bronchi, Bronchial Tree, and Lungs, "Bronchi and Bronchial Tree." Accessed May 23, 2006. http://training.seer.cancer.gov/anatomy/respiratory/passages/bronchi.html
Wikipedia, The Free Encyclopedia, Wikipedia,com, Respiratory system. Accessed May 23, 2006. www.wikipedia.org
ContributorsTeresa Ellis, Malinda Schaefer Zarske, Janet Yowell
Copyright© 2006 by Regents of the University of Colorado.
Supporting Program (Return to Contents)Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder
Acknowledgements (Return to Contents)
The contents of this digital library curriculum were developed under grants from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation (GK-12 grant no. 0338326). However, these contents do not necessarily represent the policies of the DOE or NSF, and you should not assume endorsement by the federal government.