Air Toxics Under the North Star A University of Montana Center for Environmental Health Sciences Education Outreach Project Lesson Four

Transcription

1 Air Toxics Under the North Star A University of Montana Center for Environmental Health Sciences Education Outreach Project Lesson Four Lesson Title: Understanding the Respiratory System Subjects Addressed: Science, Health Lesson Developed By: Nancy Noel Marra, CEHS Education Coordinator Grade Level: High School Class Time: 1-2 class periods Inquiry-Based Lesson (Inquiry category that best describes the level of this lesson is highlighted) Guided Inquiry Challenge Inquiry Free Inquiry Teacher provides some Teacher provides question, Students choose questions questions and/or instructions students design and implement and design and implement for investigation. experiments. experiments. Identify the Lesson s Core Understanding (Describe importance of lesson - helps maintain focus): In order to get a good understanding of air quality and how it affects respiratory health, it s important to be familiar with the respiratory system. Lesson Summary (A quick recap): Students learn the importance of studying air pollution via interactive video demonstrations. Students then construct miniature lung models using liter bottles, balloons, rubber bands, clay, tubing and hose connectors. Objectives (By the end of this lesson, students should be able to ): Explain how pollution exacerbates respiratory ailments. List the major parts of the respiratory system and describe how they work. Inclusion of Alaska Native Cultural Content American Indian and Alaska Native adults have the highest lifetime prevalence of asthma among single-race groups, according to a report released in Between 2004 and 2008, 14.2 percent of Native American adults said they had been told by a doctor that they had asthma. This was substantially higher than every other single racial or ethnic group: White (11.6%); Black or African American (11.6%); Asian (8.2%); and Hispanic (8.6%). Near present day Barrow, between 125 and 400 years ago, the home of a family was crushed by an ivu or a large section of shorefast ice. The discovery of this family (known to many as the Frozen Family of Utquagvik) established that indoor air pollution existed long before many may have imagined. Medical examinations revealed that two of the women suffered from severely blackened lungs caused by the accumulation of carbon in the lungs. These findings were attributed to inhaled smoke produced by seal oil lamps, which were used to heat and light the house.

2 Aligning with Standards (Cite Alaska Content and Performance Standards): Skills for a Healthy Life A-A student should be able to acquire a core knowledge related to well-being: 1, 5 Skills for a Healthy Life B - A student should be able to demonstrate responsibility for the student s wellbeing: 5 Skills for a Healthy Life D - A student should be able to contribute to the well-being of families and communities: 1 Concepts of Life Science C- A student should understand and be able to apply the concepts, models, theories, facts, evidence, systems, and processes of life science: 2 Preparing for the Lesson Materials/Incorporation of Technology: Website: Interactive lungs Lung Models Scissors Surgical Tubing (6 inch segment/student) Balloons (3 per student) Rubber Bands (2 per student) Modeling Clay One-Liter Bottles (enough for each student) 3-way Hose Connector Student Handout: Do-It Yourself Lung Models Diagramming Materials: Overhead Projector, Teacher Guide, Transparency of Respiratory System (with blanks), Transparency Pens (extension activity) Student Handout: Respiratory System Diagram (extension activity) Human Lung Model and/or Pig Lungs (extension activity- Request from UM) Vocabulary: Alveoli - small air-containing compartments in the lungs where the bronchioles terminate and from which respiratory gases are exchanged with the pulmonary capillaries. Bronchus (plural bronchi) - an airway in the respiratory tract that conveys air into the lungs. Capillaries - blood vessels that are imbedded in the walls of the alveoli. While in the capillaries the blood gives off carbon dioxide through the capillary wall into the alveoli and takes up oxygen from the air in the alveoli. Diaphragm - a strong wall of muscle that separates the chest cavity from the abdominal cavity. By moving downward, it creates suction in the chest to draw in air and expand the lungs. Trachea (windpipe) - the main trunk of the system of tubes by which air passes to and from the lungs in mammals. The trachea divides into two main bronchi. Adaptations for Exceptionalities (Instructional strategies and activities aligned with various learning styles and diversity of student population): Teacher can distribute respiratory system diagrams (extension activity) for students referral when constructing their lung models. Resources: Implementing the Lesson Anticipatory Set (The hook that sets the stage and is directly related to the learning at hand): Let students know that today s lesson will begin with a simple exercise. When instructed to begin, students will inhale/exhale for 10 seconds. When time is called, students multiply that number by 6 (to establish a one-minute lapse). The average resting respiratory rate for an adult is breaths per minute. What were some of our rates? (Check for answers.) I m sure some of you might have

3 Anticipatory Set (continued): breathed a little faster, or a little slower than normal. That s what s cool about the respiratory system we can control our breathing if we want. Yet, on the other hand respiration is mostly something we do all day without even thinking about it. This lesson will give us a better understanding of how the main anatomical features of this remarkable system function. Introduction (Performance standards are clearly communicated: students should be able to articulate the academic expectations and what is required to be proficient): We re all fairly familiar with the human respiratory system, but perhaps not to the extent that will be required of us during our air quality research. In today s lesson, you will be expected to work with your group to construct a balloon lung model. Body of Lesson (The use of effective and varied instructional strategies to convey the lesson s core understanding): Background Information: Step 1: Instructor begins the lesson by visiting (use the link titled Interactive Lungs). Instructor first selects the Normal Breathing (gas exchange) option to provide an overview of respiration. Instructor then follows with the Small Particles (PM 2.5 ) option. Step 2: At the end of the PM 2.5 segment, the teacher asks questions that will lead students to develop inquiries about the respiratory system and air pollution: What do you see as some possible implications from breathing in PM 2.5? (PM 2.5 is small enough to bypass the body s natural deterrents like nose hairs and cilia and can make its way deep into the lungs.) What are some sources of PM 2.5? (Dust, wood smoke, car exhaust, brush fires, mining, etc.) Why is clean air important to human health? (The human body depends on oxygen and needs to remove CO 2. This gas exchange takes place deep in our lungs so we want to keep them healthy.) Step 3: The instructor continues the discussion by providing additional information. In recent years, the link between various illnesses and air pollution has become much clearer as a result of scientific research. Air pollution can affect our health in many ways with both short-term and long-term effects. Different groups of individuals are affected by air pollution in different ways. Some individuals are much more sensitive to pollutants than are others. Young children and elderly people often suffer more from the effects of air pollution. People with health problems such as asthma, heart and lung disease may also suffer more when the air is polluted. The extent to which an individual is harmed by air pollution usually depends on his/her total exposure to the damaging chemicals, i.e., the duration of exposure and the concentration of the chemicals must be taken into account. Examples of short-term effects include irritation to the eyes, nose and throat, and upper respiratory infections such as bronchitis and pneumonia. Other symptoms can include headaches, nausea, and allergic reactions. Short-term air pollution can aggravate the medical conditions of individuals with asthma and emphysema. Long-term health effects can include chronic respiratory disease, lung cancer, heart disease, and even damage to the brain, nerves, liver, or kidneys. Particulate matter, or PM, consists of the dust, soot and smaller particles in the air. Some types of PM can be seen with the naked eye, such as soot or smoke, but many forms of PM are so small that a microscope is needed to see them. PM is directly emitted by a number of sources, including automobiles, fuel burning, and unpaved roads, but can also be formed in the air as different chemicals react. The health effects of PM include aggravated asthma, respiratory complications, and even premature death. There are other air pollutants besides particulate matter. The EPA has identified 188 hazardous air pollutants (HAPs) that it considers toxic. These HAPs include benzene (which is found in gasoline), perchlorethlyene (which is emitted from some dry cleaning facilities), and methylene chloride (which is used as a paint stripper). Examples of other listed air toxics include dioxin, asbestos, toluene, and metals

4 Body of Lesson (continued): such as cadmium, mercury, chromium, and lead compounds. People exposed to toxic air pollutants may have an increased chance of getting cancer or experiencing other serious health effects. Step 4: The instructor introduces the lung model activity and distributes the student handouts, assigns working groups, and outlines the procedure for collecting materials and completing the model. Closure (The bow that ties things up and directly refers back to the anticipatory set): As we close today, let s go back to our opening activity that gave us an idea of how often we breathe throughout the day. Now tie that in with the models we made. Can you imagine what your day would be like if you had to tell your lungs to work? Extensions (Ways this lesson can be tied to additional learning opportunities): Students can extend/enforce their understanding of the respiratory system through the included diagramming activity. The teacher can choose to use a pig lung model (real tissue) or a human lung model while conducting the lesson, or can have students work with the models afterward. Assessing the Lesson Tools (Multiple ways to provide meaningful feedback on student learning): Student made lung models Class participation Instructor Reflections (Notes to self: what worked, what didn t, etc.): Funding for the Air Toxics Under the North Star program provided by National Institute for Environmental Health Sciences (NIEHS), Grant Number RC1ES

5 Do-It-Yourself Lung Model Here's what you'll need... An OLD pair of scissors (not your mother's good ones) Six inches of surgical tubing Three good-sized balloons Two rubber bands A large lump of modeling clay A clear plastic one-liter bottle A three-way hose connector Step One: Assemble the "Lungs" Push the plastic tube into one opening of the hose connector. Use the clay to make an airtight seal. Tightly attach a balloon onto each of the other openings with the rubber bands, making sure the seal is airtight.

6 Step Two: Prepare the "Chest Cavity" Using the scissors, carefully cut off the bottom 1 inch from the bottle. Make sure the cut edge of the bottle is smooth. Place the lungs (balloons and connector) inside, and seal the plastic tube into the neck of the bottle with the rest of the clay to make an airtight fit. Step Three: Prepare the "Diaphragm" Tie a knot in the neck of the third balloon, then carefully cut it in half, crossways. Gently stretch the half of the balloon with the knot in it over the bottom of the bottle, pulling it up around the sides. Make the balloon as taut as you can - like the top of a drum. Step Four: Start breathing! Throat Lungs Diaphragm The lower part of the balloon represents the diaphragm, the main breathing muscle. Pull it down, as though you were inhaling. This lowers the air pressure in the bottle. Air from outside rushes in and makes the two balloons expand, just like the real lungs inside your chest. Activity retrieved from:

7 Extension Activity Teacher Guide - Use during Student Labeling of Respiratory System Diagram The diagram of the respiratory system shows the intricate structures needed for breathing. Breathing is the process by which oxygen in the air is brought into the lungs and into close contact with the blood, which absorbs it and carries it to all parts of the body. At the same time the blood gives up waste matter (carbon dioxide), which is carried out of the lungs when air is breathed out. 1. The SINUSES (frontal, maxillary, and sphenoidal) are hollow spaces in the bones of the head. Small openings connect them to the nose. The functions they serve include helping to regulate the temperature and humidity of air breathed in, as well as to lighten the bone structure of the head and to give resonance to the voice. 2. The NOSE (nasal cavity) is the preferred entrance for outside air into the respiratory system. The hairs that line the wall are part of the air-cleaning system. 3. Air also enter through the MOUTH (oral cavity), especially in people who have a mouth-breathing habit or whose nasal passages may be temporarily obstructed, as by a cold or during heavy exercise. 4. The ADENOIDS are lymph tissue at the top of the throat. When they enlarge and interfere with breathing, they may be removed. The lymph system, consisting of nodes (knots of cells) and connecting vessels, carries fluid throughout the body. This system helps to resist body infection by filtering out foreign matter, including germs, and producing cells (lymphocytes) to fight them. 5. The TONSILS are lymph nodes in the wall of the throat (pharynx) that often become infected. They are part of the germ-fighting system of the body. 6. The THROAT (pharynx) collects incoming air from the nose and mouth and passes it downward to the windpipe (trachea). 7. The EPIGLOTTIS is a flap of tissue that guards the entrance to the windpipe (trachea), closing when anything is swallowed that should go into the esophagus and stomach. 8. The VOICE BOX (larynx) contains the vocal chords. It is the place where moving air being breathed in and out creates voice sounds. 9. The ESOPHAGUS is the passage leading from the mouth and throat to the stomach. 10. The WINDPIPE (trachea) is the passage leading from the throat (pharynx) to the lungs. 11. The LYMPH NODES of the lungs are found against the walls of the bronchial tubes and windpipe. 12. The RIBS are bones supporting and protecting the chest cavity. They move to a limited degree, helping the lungs to expand and contract. 13. The trachea divides into the two main BRONCHIAL TUBES, one for each lung, which subdivide into each lobe of the lungs. These, in turn, subdivide further. 14. The right lung is divided into three LOBES, or sections. Each lobe is like a balloon filled with sponge-like tissue. Air moves in and out through one opening -- a branch of the bronchial tube. 15. The left lung is divided into two LOBES. 16. The PLEURA are the two membranes, actually one continuous one folded on itself, that surround each lobe of the lungs and separate the lungs from the chest wall. 17. The bronchial tubes are lines with CILIA (like very small hairs) that have a wave-like motion. This motion carries MUCUS (sticky phlegm or liquid) upward and out into the throat, where it is either coughed up or swallowed. The mucus catches and holds much of the dust, germs, and other unwanted matter that has invaded the lungs. You get rid of this matter when you cough, sneeze, clear your throat or swallow. 18. The DIAPHRAGM is the strong wall of muscle that separates the chest cavity from the abdominal cavity. By moving downward, it creates suction in the chest to draw in air and expand the lungs. 19. The smallest subdivisions of the bronchial tubes are called BRONCHIOLES, at the end of which are the air sacs or alveoli (plural of alveolus). 20A. The ALVEOLI are the very small air sacs that are the destination of air breathed in. 20B. The PULMONARY VEIN carries blood away from the lungs. 20C. The CAPILLARIES are blood vessels that are imbedded in the walls of the alveoli. While in the capillaries the blood gives off carbon dioxide through the capillary wall into the alveoli and takes up oxygen from the air in the alveoli. Blood is brought to the capillaries by the PULMONARY ARTERY and taken away from the capilllaries by the PULMONARY VEIN. 20D. The PULMONARY ARTERY brings blood to the lungs via the capillaries. Material retrieved from:

8 Answer Key for Extension Activity - Respiratory System Diagram Graphic retrieved from:

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11 Extension Activity: Pig Lungs Model Kit Materials Model components Tray PVC pipes Pump Hose Two sets of pig lungs: one healthy and one slurried to simulate a smoker s lungs Cross section of lung Kit booklets 1. Teacher s guide for healthy lungs 2. Teacher s guide for smokers lungs 3. Booklet describing effects of smoking VHS Video Directions for Set-up Tray 1. Attach the two vertical PVC pipes to bottom of tray 2. Attach the crossover PVC pipe to the two vertical beams (this horizontal bar is used to hang the lungs for viewing) Pig Lungs (from a 250 lb pig) 1. Attach to crossover PVC pipe Pump 1. Attach hose to the inflate hole of the pump 2. Attach other end of hose to the PVC joint (pump is used to inflate the lungs, simulating the diaphragm) 3. No worries about overinflating; impossible to do 4. No formaldehyde has been used; rather propylene glycol (use gloves while handling; allows students to feel real tissue) Demonstration 1. Talk about the respiratory system 2. Discuss the cross-section (shows the inside of lung and the alveoli) 3. Pass around for observation 4. Show the healthy pig s lung & explain how the pump is simulating what the human diaphragm does (muscle below the lungs) 5. Point out the lobes right & left & also the pig s unique lobe (different from humans) 6. Point out that human lungs are never as fully inflated as in this demonstration 7. Show trachea - where the oxygen comes in & carbon dioxide is exhaled (discuss the interdependence between plants & people) 8. Ask students what it is that makes these lungs look healthy (color, the way they inflate) 9. Change the model to the smoker s lungs 10. Ask students what it is that makes these lungs look unhealthy (color, they don t completely inflate due to the tumor) 11. Explain that the lungs have been injected with a carbon slurry and a tumor added to simulate a smoker s lungs (pack/day for 20 years) Maintenance 1. Can superglue or sew any holes that may incur 2. Never use water to wash the lungs 3. When returning to the plastic container, be sure they re kept moist (use the pink liquid - the fluid is pink due to dye, not because it contains blood)

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