Backgrounder for Teachers
As genetically-engineered crops become increasingly present at the grocery store and in farmers' fields, understanding the issues related to this practice takes on a greater importance. What exactly are we eating? Is it harmful to our health? Is it harmful to the environment? How is it regulated? What benefits are there to genetic engineering?
The 10/4/02 broadcast of NOW WITH BILL MOYERS also provides a 20-minute in-depth report on the potential benefits and dangers of genetically-modified foods. Educators may tape the broadcast off-air and use it in the classroom for one year. If you missed the broadcast, take a look at the free transcript of the report on the NOW Web site for helpful background information in teaching this lesson. If you would like to purchase a copy of the broadcast, it is available for a nominal cost from ShopPBS.
Finally, the Related Resources section of this lesson points to additional Web sites related to this topic.
Assumed Student Prior Knowledge
It is assumed that students already understand the basics of heredity and Mendelian genetics, as well as the structure and function of DNA.
Part One: What is Genetic Engineering?
1. Display some examples of foods that have been genetically-engineered with those that have not been. (Some grocery stores voluntarily label produce that has been genetically-engineered. Most genetically-modified foods are included as ingredients in processed foods. A list of foods with such ingredients is provided by Greenpeace's True Food Network. If actual samples of genetically-modified foods are not available, display photos and descriptions from the Internet. Try the True Food Network site, the sites at the end of this lesson plan, or a search engine.)
2. Ask students if genetically-engineered foods look, smell or taste any different from those that are not genetically-modified. What makes genetically-modified foods distinctive? Why would biologists attempt to do this kind of work?
3. Group students into teams of four and ask them to visit some of the following sites to find out the steps for how genetic engineering is done. Use the "What is Genetic Engineering?" handout (PDF file) to help direct student note taking. Allow about 20 minutes for research.
4. Next, have teams produce a poster, concept map, or other creative presentation to explain how genetic engineering is done. Some groups might choose to write a song, do a small skit, or act out the process. Each team should plan to display and explain their creative presentation at the beginning of the next class period. If you feel the students need more time to work, feel free to set the presentation date for a later time.
Part Two: What Are the Benefits and Risks of This Procedure?
1. Show the NOW WITH BILL MOYERS video segment. Students should be keyed to watch for possible benefits and dangers related to genetically-modified foods. In addition, ask students to listen for the term "biodiversity" and be able to explain what it means.
2. After watching the video, work as a class to brainstorm a list of pros and cons related to the use of genetically engineered crops. (Note: The NOW Web site also provides Pro and Con debates from the Johannesburg Earth Summit.)
3. Next, ask the class to pair up the pro and con positions that relate to a specific argument. Then, prioritize the pros and cons based on which issues they think are most important. Feel free to make your own selections if you think students are missing an important idea. During this discussion, have students take notes on the Pro/Con handout (PDF file) for students. You can use the Pro/Con handout for teachers (PDF file) or the Web sites to ensure students capture key issues.
4. The same teams from Part One should select one of the pro and con pairs and research the evidence and ideas behind it. They should look at both sides regardless of their personal views on the subject. This research can be done outside of class, with students dividing up responsibilities. As they conduct research, students should take notes on their topics and cite the sources they used for information. Now is a good time to remind students how to obtain reliable sources and look for media bias.
5. When the research has been completed, each team should select two members: One to present the supporting argument and one to present the other side. Presentations should take no longer than 5 minutes per group. Each student presenting can have one minute without being interrupted. After this time, the students presenting can engage in a one on one discussion for the remaining three minutes. Allow each group about a week to complete their research and to practice their presentation.
Part Three-Forming Your Own Opinion
Read the quote below to the class and ask them to think about how it applies to genetically-modified foods.
"Your scientists were so pre-occupied with whether or not they
could, they didn't stop to think if they should." (Jurassic Park 1993)
1. Use the Think-Pair-Share approach to draw out student reactions to the quote in connection with the practice of genetically-modified foods. This step also serves as a helpful pre-writing activity.
2. Next, ask students to write a short paper expressing their personal feelings about genetically-modified foods. They should support their position using evidence provided from the Web sites, video, and discussion.
Part One Assessment: Each group will receive the same grade
Part Two Assessment: Each group will receive the same grade.
- 25 points for creativity of approach
- 50 points for accuracy and order of the steps (Each student should also submit
research notes for review.)
- 25 points for poise and presentation
Part Three Assessment: Paper
- 25 points for presentation of evidence on both sides of the issue
- 25 points for accuracy of information (Each member of the group should submit
his or her individual research on the topic.)
Grading will be 75% on evidence and defense of their position, 25% on grammar and spelling. Remind the class that there is no one right answer and they do not have to agree with what they think the teacher wants to hear.
1. For additional study of the effect of monoculture on biodiversity, see the lesson plans provided by The American Field Guide on PBS Online.
2. Teachers of younger students might want to skip part one of this lesson plan or do it together as a class activity.
3. Teachers with a large number of ESOL students will find that forming teams for oral presentation alleviates much of the stress on Non-English speaking students.
Below are some sites that provide useful information related to this lesson's topic. The NOW site has additional Web site recommendations that may be of interest.
This site from the National Health Museum contains lots of references and background information to explain biotechnology processes. In addition, there are many lesson plans that teachers can use to extend this topic.
Risks of Genetic Engineering
This site, organized by the Union of Concerned Scientists, examines potential harms to health, potential environmental harms, and general risks related to genetic engineering.
Genetic Engineering: Fast Forwarding to Future Foods
This is a reprint of an Food and Drug Administration (FDA) publication that explains the regulation guidelines and addresses the advantages and challenges of genetic engineering.
Ag BioTech InfoNet
This site is full of periodicals on biotech, nicely categorized by topic for easy navigation (environmental impacts, health risks, industry news, links to related sites, message boards, new developments, etc.), and updated daily.
Pew Initiative on Food and Biotechnology
This site was established to be an independent and objective source of credible information on agricultural biotechnology for the public, media and policymakers. It supports informed public dialogue on ways that the regulatory system may need to evolve to address the issues posed by the anticipated development of this new technology and the growing body of scientific knowledge.
Center for Food Safety and Applied Nutrition
This site from the FDA posts proposed, pending and final rules and policies regarding food biotechnology.
About the Author
Claudia Fetters is a 21-year veteran of science education, having taught biology, earth science and astronomy during her career. She currently teaches at Westfield High School in Chantilly, Virginia. She also works with a group at Purdue University to develop instructional CD's on biology topics.