The Genetic Engineering of BT Corn

By Colleen McGannon • Leslie Hadaway

Grade Level	10th
Subject Area	Biology - Genetics
Duration	Four 50-minute classes
Background Knowledge	The corn crop was being destroyed by the corn borer. Farmers were losing money. Genetic engineering was used to address the problem. A bacterial toxin gene was introduced into the corn. Thus, the corn pollen now produces a bacterial toxin that will kill the corn borer, saving the corn crop. This toxin will not kill humans. Scientists did a study to determine if the corn pollen harmed nearby non-target organisms, specifically the monarch. The monarch was caged and its only food source was the pollen. The monarch died. Animal rights activists protested the use of corn by dressing up as monarchs at rallies. Since then, several studies all over the world have shown that when its natural environment, monarchs don't eat the pollen and are safe. Yet, it is hard to get society to believe this new data.
Author	Colleen McGannon and Leslie Hadaway

Summary
Students will review what they have learned about DNA and genetic engineering. After discussing how the natural pesticide was genetically engineered into the corn, students, guided by a worksheet, will go through the paper in which the initial scientist showed that the neighboring monarch was killed after eating corn pollen, after which, a social protest ensued. Students will design their own hypothetical experiment to verify or disprove this initial study. The next assignment will include filling out a worksheet individually regarding a paper that criticized the initial study. Students will subsequently participate in a debate. The debate will consist of four student groups: one will act as farmers, one as scientists (saying the monarchs will die), one as scientists (saying that the monarchs may live), and one as the protestors.

Objectives
Upon completion of this lesson, students will be able to: Cite one example of a genetically modified food. Explain that the corn was genetically modified in response to the corn borer’s destruction of the corn crop. Look at a picture of a protest and describe that the people are dressed up as monarchs in order to prevent foods from being genetically modified. Describe the initial study that addressed the effect on the monarch. Design an experiment to determine the effect that the genetically modified corn pollen will have on the monarch. Participate in a debate on the genetic engineering of corn.

Mateirals Required
Worksheet, computers, published papers Published papers: (1-2 pages each): Losley, Transgenic pollen harms monarch larvae. Nature. 399, 214 (1999) and Hodgson, Monarch Bt-corn Paper Questioned. Nature Biotechnology 17, 627 (1999). Websites: US Department of Agriculture University of Kentucky, Department of Entomology Greenpeace Biotech-info

Ohio Standards

Life Sciences
Benchmark J: Summarize the historical development of scientific theories and ideas, and describe emerging issues in the study of life sciences.
Science and Technology
Benchmark B: Explain that science and technology are interdependent; each drives the other.
Scientific Inquiry
Benchmark A: Participate in and apply the processes of scientific investigation to create models and to design, conduct, evaluate and communicate the results of these investigations.
Scientific Ways of Knowing
Benchmark A: Explain that scientific knowledge must be based on evidence, be predictive, logical, subject to modification and limited to the natural world
Benchmark C: Describe the ethical practices and guidelines in which science operates