Standards Aligned

Science

• HS-LS1-1. Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.
• HS-LS2-6. Evaluate the claims, evidence, and reasoning that the complex interactions in ecosystems maintain relatively consistent numbers and types of organisms in stable conditions, but changing conditions may result in a new ecosystem.
• HS-LS2-7. Design, evaluate, and refine a solution for reducing the impacts of human activities on the environment and biodiversity.
• HS-LS3-1. Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring.
• HS-LS4-1. Communicate scientific information that common ancestry and biological evolution are supported by multiple lines of empirical evidence.
• HS-LS4-4. Construct an explanation based on evidence for how natural selection leads to adaptation of populations.

Language Arts (Common Core)

• RST.11-12.1. Cite specific textual evidence to support analysis of science and technical texts, attending to important distinctions the author makes and to any gaps or inconsistencies in the account.
• WHST.9-12.2. Write informative/explanatory texts, including the narration of historical events, scientific procedures/ experiments, or technical processes.
• WHST.9-12.9. Draw evidence from informational texts to support analysis, reflection, and research.
• SL.11-12.5. Make strategic use of digital media (e.g., textual, graphical, audio, visual, and interactive elements) in presentations to enhance understanding of findings, reasoning, and evidence and to add interest.

Learning Objectives

• Understand the basic structure of DNA and its role in genetic inheritance.
• Comprehend how DNA encodes traits that are passed across generations.
• Understand what a genetically engineered or (GMO) is.
• Understand that PCR is a technique for amplifying specific parts of the genome.
• Understand that seed selection and breeding can be used to alter traits in crops.
• Understand how genetic engineering can be used to alter existing traits or introduce novel traits in crops in a faster and more targeted fashion.
• Discuss implications of genetically engineered plants for society.

Materials

Graduates of the Seed to STEM 2.0 High School track can request supplies to teach lab for free.

• MiniPCR GMO Learning Lab: Heart-Shaped Bananas
• MiniONE Gel Electrophoresis
• MiniONE PCR Machine (link to order)

Safety Considerations

Be aware of student allergies or seeds treated with chemicals.

Procedures for Instruction

Length of Time for Preparation: 20 minutes
Length of Time for Classroom Teaching: 90 minutes

Preparation Procedure

See preparation pages 11-13 from MiniPCR GMO Lab Instructor’s Guide.

Background Information

Pages 2-5 of the MiniPCR Lab Guide provides background information. Also, rely on previous Seed to STEM biotechnology labs for additional background information.

Classroom Discussion

Introduce the topic and assess students for prior understanding. These questions can also be found on page 15 of the student’s guide.

• How does genetic diversity of plants arise through natural selection?
• How and why do humans selectively breed crops?
• What is a GMO?
• How can new genes be introduced into a plant?
• Does the introduction of new genes into an organism ever occur in nature?

MiniPCR GMO Lab

The MiniPCR GMO Lab procedure will be used with the following alterations of instructions from the miniPCR GMO Lab procedure. The following pages referenced below are from the miniPCR student’s guide.

• On page 3, Corn Crop Transgenic Modified – 85%, the data table shows the percentage of specific crops that are transgenic. The table emphasizes corn, and that is what this lab will specifically be testing for as a transgenic food item.
• On page 4, Creating a GMO Product using Ti Plasmid [CaMV35S promotor/Transgene/NOSTerminator], there is an explanation of how the specific GMO cassette that we are going to attempt to test for is constructed in order to create a transgenic plant. We will be targeting the 35S promotor and the positive plant control (Tubulin) for this lab.
• On page 5, Explanation of the PCR and Electrophoresis Lab, we will follow these instructions to determine if common food items have been genetically modified, and this section will demonstrate how this complete lab will detect a GMO food.
• On page 6 (recommended foods to test: corn tortillas, tortilla chips, Doritos, Cheetos), we will specifically attempt to test just the corn products listed in that table.
• On pages 7-8, DNA Extraction Procedure, we will follow that exact procedure on DNA extraction from the selected food items being tested.
• On pages 8-9, PCR set up instructions, we will follow the directions to set up the PCR reactions.
• On pages 10-11, Setting up and running the PCR machine, we will follow the directions as written. Also, we will be using a 2.0% gel instead of the 2.4% gel the procedure calls for.
• On page 13, Photographing and Interpreting the Gel, we will follow this procedure to get an image of the completed gel and how to interpret the gel.
• On pages 15-17, Lab Questions and Extension Activities, we will be using the Lab Report Extension to assess what the students have learned from completing this lab activity.

Teacher Resources

• GMO Answers
  Website is the #1 resources for to help with this lab and to answer GMO answers.
• www.fda.gov/feedyourmind
  Provides additional information about agricultural biotechnology.
• Your Genome  What is PCR(polymerase chain reaction)?
  Easy to understand website explains what PCR is and how it is used in the field of genetics.
• miniPCR Bio  What is PCR? Polymerase Chain Reaction
  Great video explaining the process of PCR and the miniPCR used for this lab.
• Khan Academy  Polymerase Chain Reaction
  Notes/Reading outlining what PCR is and how we use it in laboratories.
• Amoeba Sisters Gel Electrophoresis
  This video introduces gel electrophoresis and how it functions to separate molecules by size.
• U.S. Food & Drug Administration  Agriculture Biotechnology
  Numerous pertaining to how GMOs are identified, regulated, their history and impact on the world.
• Plant and Soil Sciences eLibrary  GMO Detection
  This site contains a video that walks viewers through the use of GMOs to prolong the shelf life of tomatoes.

Lab Analysis

See pages 12-14 of the miniPCR GMO Lab instructions to determine if you have detected any GMOs in the foods tested.

Reflection and Conclusion

See the below questions have been modified using the study questions found on pages 16-17 of the student’s guide. These questions can be used for reflection or assessment.

• What do the results suggest about your test foods?
  • Do they contain genetically engineered sequences?
  • What data evidence supports your answer?
• Are your results consistent with your expectations about these foods?
• Describe two transgenes that are commonly introduced into crops.
  • What purpose do this genetic modification have?
• Describe three ways in which genetically engineered crops may protect the environment.
  • Describe three ways in which they may harm the environment.
  • How do you think growing GMOs can accelerate the selection of herbicide-resistant weeds?
• Human health may be improved by GMOs.
  • How can they aid in nutrition?
  • How can they help feed a growing human population?
  • What might be the risks to manage?
• Pollen contains the complete genetic material of the plant and is airborne. Describe ways in which the spread of transgenes via pollen can be contained.

Extension Activity

There are only 10 GMO crops available in the United States today: Corn, Soybeans, Cotton, Canola, Alfalfa, Sugar Beets, Papaya, Squash, Potato, and Apple.

Food companies use labels on food to help market their products. Non-GMO labels are becoming common to help market food to consumer who are afraid of GMOs. Yet, many of these labeled food products were not made from foods that have a GMO variety.

Have students visit their local grocery store or have them look through their kitchen cabinets at home. Have them write down a list of 10 food products that are labeled as non-GMO. Have the students discuss their findings as a group.

• Were these products made from one of the 10 GMO crops available in the United States?
• It is appropriate to have the non-GMO label?
• Which products that do have a non-GMO label were made from a crop that has a GMO variety?

Assessments

To assess learning, the students will follow the extension instructions on page 17 of the miniPCR GMO lab instructions.

Lab Report – report on the findings of the written lab.

• Title
• Introduction
• Materials
• Procedure
• Results
• Discussion

Sources

MiniPCR GMO Learning Lab: Heart-Shaped Bananas

Disclaimer

Any educator electing to perform demonstrations is expected to follow NSTA Minimum Safety Practices and Regulations for Demonstrations, Experiments, and Workshops, which are available at https://static.nsta.org/pdfs/MinimumSafetyPracticesAndRegulations.pdf, as well as all school policies and rules and all state and federal laws, regulations, codes and professional standards. Educators are responsible for abiding appropriate legal standards and better professional practices under a duty of care to make laboratories and demonstrations in and out of the classroom as safe as possible. If in doubt, do not perform the demonstrations.