To explore how the immune system functions in a variety of allergic reactions.
Knowledge of health and knowledge about illness are closely connected. Our knowledge of diseases has helped us understand how the healthy body works, which, in turn, helps us to define and detect illnesses. (Benchmarks for Science Literacy, p. 143.) In middle school, students should have had experiences studying the healthy functioning of the human body. Students should also have developed understandings of how organs and organ systems work together. (Benchmarks for Science Literacy, p. 137.) In high school, students should relate their knowledge of normal body functioning to situations in which functioning is impaired due to environmental or hereditary causes. Also at this level, students should try to find explanations for diseases in physiological, molecular, or system terms. Since the primary purpose of this lesson is to explore the role of immune responses in allergic reactions, students should already have a working knowledge of body systems, and the immune system in particular.
Begin the lesson by engaging the entire class in a discussion guided by the following questions:
- Do you know someone who has had an allergic reaction? What is that person allergic to?
- What causes the allergic reaction? Does everyone have an allergic reaction to that substance?
- Can you describe what happens to the person when they have an allergic reaction?
The purpose of the discussion is to elicit student responses and to help you find out what your students think about the ideas related to the central benchmark. Do not correct their ideas in the discussion. In the course of the lesson, they will have the opportunity to revise their ideas based upon what they have learned. After the class discussion, have each student answer the following questions in their science journals.
- How would you explain to someone what an allergy is?
- How would you describe what happens in the body to cause an allergic reaction?
In this investigation, students will assume the role of health writers preparing a special section for the school newspaper on allergies. To introduce the lesson, bring to class (or ask students to bring to class) a variety of newspaper or magazine articles that deal with health topics. Discuss the sample articles and rate and/or evaluate them in terms of their use or misuse of supporting evidence, the language used, and the logic of the argument presented. Explain to students that these are some of the characteristics by which scientifically literate individuals should be able to evaluate scientific information in the media.
You might want to develop a rubric for critiquing the newspaper articles based on this activity. The same rubric could be used later to assess student articles.
For more ideas about evaluating scientific information in the media, see Habits of Mind: 12E Critical Response Skills. (Benchmarks for Science Literacy, p.298-300.)
Prepare the students for the task by saying, "In this activity, you will write a newspaper article on allergies. As a reporter, you need to do some basic background research. You want to be clear about your own understanding of what an allergy is and who is at risk so that you can better explain it to your readers. During your search for background information, you may come across a question that intrigues you for your article."
Have each student begin their research by reading All About Allergy, on the Allernet website. As they read, have them answer the following guiding questions in their science journals.
- What does the immune system do when it encounters an allergen?
- What is the allergy antibody?
When all students have had an opportunity to read the selection and answer the questions, briefly discuss the answers with the class.
Divide the class into small groups, or news teams. Say to the students, "As you were reading about allergies, you probably found a number of allergic reactions that interested you. Your group's first task is to select one topic that you will all work on together. Share your ideas with the members of your team and decide on a topic. Then you will continue to research your topic. After you have completed your research, each group will make a poster that explains the body's immune response to the allergen you have chosen in two ways: show the symptoms produced by the response and show what happens at the cellular level." The poster will be used to check student understanding, but it should also be used as an illustration in the team articles.
To help the groups select a topic, have them read What Are Allergies and Who Is at Risk? on the Intellihealth website. This article provides information about the role that the immune system plays in allergic reactions, including the fact that contact with an allergen triggers production of the antibody immunoglobulin E (IgE), which causes immune cells in the mucous lining of your eyes and airways to release inflammatory substances, including histamine.
Sometimes in cooperative learning, not all students are assessed individually. Nonetheless, it is important that all students show understanding of the benchmark ideas and can communicate these understandings. Since the students will be working as a news team, members may have different roles. Some students may choose to work as writers or editors, some as graphic designers, and some as field reporters who gather basic information through research and interviews. In order to assess each student individually, ask that each team member keep a log that details their individual tasks and explains how their role contributes to the overall goal of the project.
Regardless of the topic selected, the student article should explain in terms that general readers can understand the following two points: the role of the immune system in allergies and why one person may have an allergic reaction and another doesn't. The students should conduct their research on the Internet using several of the following Web resources. These should be cited in a reference list. Students can also conduct interviews with people who have allergies and with health professionals who treat patients with allergies. Students may want to make up catchy titles for their articles, such as the following:
- Food Allergies or "Hard to Swallow"
- Pet Allergies or "Don't Get Your Dander Up"
- Latex Allergies or "Don't be Caught Red-handed"
- Allergy and Heredity or "Dusty Genes"
- Hay Fever and Pollen Allergies or "Hopelessly Allergic to You"
For their research, in addition to the websites already discussed, you can direct students to these Web resources:
- Fast Facts: Allergies and Allergy Statistics, from the American Academy of Allergy, Asthma, and Immunology, contain referenced statistical information that students can use in their articles.
- Allergist, a site maintained by allergists, the medical specialists who treat allergies and asthma, and their professional association, the American College of Allergy, Asthma & Immunology.
- National Heart, Lung, and Blood Institute is a source for information about asthma.
- KidsHealth.org's All About Allergies and Learning About Allergies are articles targeted specifically to younger audiences and their parents.
- Mayo Clinic Health Oasis contains an Allergy Center with many articles and fact sheets.
- Understanding Cancer: The Immune System, from NIH’s National Cancer Institute, provides very sophisticated concepts that are beyond the benchmarks but that might be useful as teacher background or for use with students in advanced biology classes.
Though much of this project can be done outside of class, allow some class time for the groups to work together. Use this time to view student work in progress. You can assume the role of "chief science editor" to provide constructive feedback to the groups.
Students can present their final articles in a variety of formats, including print or webpages. However, assessment should be based on how well their articles explain the physiological aspects of their topics (i.e., an explanation that is based on the body's immune responses to allergens, as well as use or misuse of supporting evidence, the language used, and the logic of the argument presented).
It is also important that their presentations are clear, use illustrations appropriately, and explain any terminology used at a level that is comprehensible to lay audiences.
When they have completed their lessons, students should reflect in their journals about what they know now that they did not know before the lesson. Also, give students the opportunity to reflect on and revise the answers in their journals to the two questions in the Motivation section of the lesson: How would you explain to someone what an allergy is? How would you describe what happens in the body to cause an allergic reaction?
Have students read the article called The Nobel Prize in Physiology or Medicine 1996 on the Nobel Foundation website. By following the links in this article, students can read about the Immune System and the research conducted by Peter C. Doherty and Rolf M. Zinkernagel, who won the Nobel Prize for Physiology in 1996 for their discoveries concerning the specificity of the cell mediated immune defense.
Students can view and make graphical comparisons about allergies and immune system disorders using information from the National Center for Health Statistics FastStats resource. Comprehensive statistical information can be downloaded as PDF files and used by students to compare the incidence of various allergies and other immune system disorders. Students can report data based on demographic categories such as age, gender, and geographic region.