Grade Level & Subject: Grades 5-8; Health, Science
Length: One class period
After completing this lesson, students will be able to:
● Understand how human lungs work and why breathing is a necessary function.
● Identify the different parts of the human lung and explain what each does.
● Recognize the dangers of air pollution
● Describe ways to improve air quality and reduce the risk of pollution-affected respiratory complications to the population.
National Standards Addressed:
This lesson addresses the following National Health Education Standards are from the American Cancer Society:
● Content Standard: NPH-H.5-8.1 HEALTH PROMOTION AND DISEASE PREVENTION
Students will comprehend concepts related to health promotion and disease prevention:
Analyze how environment and personal health are interrelated.
Describe ways to reduce risks related to adolescent health problems.
Describe how lifestyle, pathogens, family history, and other risk factors are related to the cause or prevention of disease and other health problems.
This lesson addresses the following National Science Education Standards from the National Academies of Science.
● Content Standard: NS.5-8.3 LIFE SCIENCE
Structure and function in living systems
Regulation and behavior
● Overhead projector
● Plastic cups
● Small and large balloons
● Rubber bands
● Various materials to modify lung model, such as: clips, fasteners, glue, tape, cotton, gelatin, water, corn starch, sand/dirt etc.
● Reproducible #1 – Diagram of Lungs
● Reproducible #2 – How Lungs Work
● Reproducible #3 – Pollution and Our Lungs
● Reproducible #4 – Diaphragm Model
Students will be assessed through the following activities:
● Participation in class discussion.
● Ability to create the model of the lungs.
● Creativity in modifying the model to show the affects of air pollution.
● Air Quality Index (AQI): A metric for reporting the daily air quality, factors how the clean or polluted the air is and what associated health effects might be of concern.
● Asthma: A chronic lung disorder that is marked by recurring episodes of airway obstruction (as from bronchospasm) manifested by labored breathing accompanied especially by wheezing and coughing and by a sense of constriction in the chest, and that is triggered by hyperreactivity to various stimuli (as allergens or rapid change in air temperature).
● Carbon Monoxide: A single carbon atom bound to a single oxygen atom; CO is a colorless and odorless, but deadly if inhaled in large quantities. CO is produced during the incomplete combustion of carbon-based fuels.
● NOx: A group of compounds consisting of one nitrogen atom and 2-4 oxygen atoms. Being very unstable, they heat of the sunlight causes them to react with other gases, forming ground level ozone. NOx molecules are produced during the combustion of carbon-based fuels.
● Ozone: A triatomic very reactive form of oxygen that is a bluish irritating gas of pungent odor. It is a major air pollutant in the lower atmosphere but a beneficial component of the upper atmosphere, and is used for oxidizing, bleaching, disinfecting, and deodorizing.
● Particulates: Of, relating to, or existing in the form of minute separate particles (dust, smoke, and other particulate matter).
● Pollution: A substance that makes land, water, air, etc., dirty and not safe or suitable to use; something that causes pollution.
● Respiratory System: A system of organs functioning in respiration and consisting especially of the nose, nasal passages, nasopharynx, larynx, trachea, bronchi, and lungs.
● Smog: A fog made heavier and darker by smoke and chemical fumes; also: a photochemical haze caused by the action of solar ultraviolet radiation on atmosphere polluted with hydrocarbons and oxides of nitrogen especially from automobile exhaust.
● SO2: A sulfur atom attached to two oxygen atoms; changes the pH of precipitation in the atmosphere. Produced from the combustion of carbon fuels that also contain sulfur (typically coal).
● Vital Lung Capacity: How much air a person can exhale in a single breath.
Respiration is the process of breathing, including inhalation, gas exchange, and exhalation. Inhalation occurs when the diaphragm and intercostal muscles (those are the muscles between your lungs and out the airways
At the end of each bronchiole are air sacs called an alveoli. In these, there is much oxygen after inhalation. In contrast, the blood in the capilaries that cover the alveoli there is much carbon dioxide. The concentrations are so different, oxygen passes or diffuses across the alveolar membrane into the capillaries, and carbon dioxide diffuses into the air sacs, which is then exhaled. The oxygen in the blood binds to hemoglobin molecules, and is carried away to parts of the body that need oxygen.
Fine particulates are emitted from the diesel engines of buses and trucks and are breathed into the lungs. NOx molecules come from combustion engines and reacts in the air to form ground level Ozone, which oxidizes lung and crop cells, making them less efficient. SO2, which comes from the burning of carbon-based fuels that also contain sulfur (typically coal), causes acid precipitation. Carbon monoxide arises from cigarette smoke and automobile exhaust fumes. It enters the blood system like oxygen, but cannot be accepted by the cells that need oxygen, and thus the hemoglobin cannot get rid of it. This poisons the blood and prevents our body from getting enough oxygen.
These pollutants all reduce visibility and irritate the lungs, making it harder to breathe and worsening problems initially caused by asthma, bronchitis, cardiopulmonary maladies, and emphysema. "The pollutants affect the lungs by causing inflammation or irritation of the airway lining," said Dr. Joseph T. Cooke, associate professor of clinical medicine and patient safety officer at New York-Presbyterian Hospital/Weill Cornell Medical Center. "More mucus and phlegm is produced, and small muscles surrounding the airway respond by squeezing down. The work of breathing increases, and it becomes more difficult to get oxygen into the body."
● Transportation and Air Quality U.S. Environmental Protection Agency
Provides an overview of pollutants and their sources in the US, information about how the
consumer can reduce pollutions and be a greener driver, modeling, testing, and research
information, as well as links for state air quality and transportation issues.
● Human Health & Environmental Affects of Emissions from Power Generation U.S. Environmental Protection Agency
Details how different pollutants from carbon-based fuels affect human health and our
● No Idling Earth Day Network
Lesson plans and resources for teaching about air quality issues and the affects of air
Warm-up: Learning about Lungs
- Begin this lesson by explaining to the students how lungs work. On an overhead projector, show the diagram in Reproducible #1 – Diagram of Lungs, and pass out Reproducible #2 – How Lungs Work
- Ask for student volunteers to come up to the projector one at a time to point to the different parts of the lungs, and then read aloud from the handout what each part does.
- Once all the parts have been identified, explain how the respiratory system works using the information in the Background Information section. While explaining, point to each relevant part of the respiratory system as you talk about it. T the diaphragm is a large muscle that contracts and relaxes involuntarily. When it contracts, it pulls down, and other muscles expand the rib cages. This creates a low air pressure state in the lungs, causing air to be sucked in through the airways to restore air pressure. Then the diagphragm relaxes upward, the rib cages relax, and air is forced back out of the lungs. During this breathing process, oxygen and carbon dioxide must be exchanged with the blood. Oxygen-rich air travels through the bronchioles during inhalation and fills the alvioli clusters at the end of each tiny branch. The alvioli are covered with capillaries filled with blood rich in carbon dioxide (a waste product of our body) and lacking in oxygen. The oxygen molecules pass through the walls of the alvioli and the capillaries, taking the place of the carbon dioxide, which passes through the opposite direction into the alvioli. The carbon-dioxide is then exhaled.
- (OPTIONAL) This would be a good time to point out that oxygyen is produced by plants by taking in the carbon dioxide that we exhale; we have a symbiotic relationship (we rely on each other).
Activity One: Building Lungs and How Air Pollution Affects Them
- Now that students understand how the respiratory system works, they will create their own models of lungs. Divide students into pairs, and hand out Reproducible #4 – Diaphragm Model along with all materials listed (Please see the materials section of Reproducible #4 – Diaphragm Model).
- Have students read the instructions aloud and allow time for any questions.
- Supervise students as they create their models.
- Once students have finished constructing their models, ask them to draw a diagram of their creations on the back of their worksheet. Have them label what each part represents.
- When students have finished, ask for volunteers to explain what each part of the model represents.
- Now, hand out Reproducible #3 – Pollution and Our Lungs and explain to students some of the problems that pollution causes for our ability to breathe and our bodies’ ability to transport oxygen. Review the reproducible with students making sure they understand the different ways pollution can harm the respiratory system. Ask the following questions:
- Why is air pollution bad? Answers should address concerns about health affects like asthma and irritation to the respiratory system.
- How can it be harmful and dangerous to our health? Pollutants can get into the airways and irritate the tissues, causing irritation, inflammation, and increased mucus production. CO can replace oxygen in our lungs, making it more difficult for our organs to get oxygen.
- For whom is air pollution worst?
- Ask students to get into their pairs again and, using various materials such as fasteners, glue, tape, water, corn starch, etc. students will modify their lung model to exemplify what occurs when pollution interrupts our ability to breathe. When students have finished, ask each pair to demonstrate their model and explain how pollution has affected it. NOTE: Materials will not perfectly exemplify the affects of pollutants, but students should be creative and seek to be more symbollic than trying to reproduce the physical affects of pollution.
Wrap Up: Brainstorming Solutions
- Ask students what they have learned. Ask for volunteers to summarize how the lungs work, where pollution comes from, and how it affects our respiratory system.
- Ask students to think about sources of air pollution in their areas.
Depending on location, sources may vary, but common answers will include cars, buses, trucks, lawn mowers, and coal power plants.
- Challenge the class to brainstorm ways in which people can protect their respiratory systems from adverse effects of air pollution. Answers will vary, but may include: recognizing the risk factors and symptoms, monitoring the Air Quality Index and appropriately limiting outdoor exposure during times of high air pollution, exercising in the morning before ozone levels build, avoiding roadsides when exercising during smog season, and various strategies for reducing air pollution such as reducing the volume of traffic through carpooling and work-at-home programs, cleaning up or preventing emissions, using alternative transportation or alternative fuels, etc.
Extension: Take Action
- Encourage students to talk to their parents about reducing their fuel use by driving less, taking public transit, and not idling. Encourage them to also talk to any family members who may have respiratory problems about how air pollution could agitate their condition. To go a step further, have kids write letters to the Education Board or their congressmen, asking them to support no idling policies or clean air legislations, respectively.
Over the course of this lesson, students gained a basic understanding of how the human respiratory system works. Students can now identify the parts of the lungs and explain the functionality of each major part. To reinforce these concepts, students built models of the lungs followed with a discussion about how pollution affects the respiratory system. Students gained insight into how air pollution is created, as well as the relationship between air quality and human health. Students brainstormed ways to improve air quality and help reduce air pollution.
LESSON PLAN CREDITS
The Clean Air Campaign, Inc. – Author
Nicole Holstein – Contributor
Education Intern, Earth Day Network
Maggie Ollove – Editor
Education Associate, Earth Day Network