Download POGIL Activity: Genetically Modified Foods

POGIL Activity: Genetically Modified Foods
Name ____________________________
Date ________________
Period _____
Genetically modified foods have had foreign genes (genes from other plants, animals or
bacteria) inserted into their genetic codes through a process known as genetic
engineering. Combining genes from different organisms is known as recombinant DNA
technology, and the resulting organism is said to be genetically modified (GMO),
genetically engineered, or transgenic. GM products include medicines and vaccines,
foods and food ingredients, animal feed, and fibers.
Objectives:
1. The learner will be able to investigate and analyze the genetic engineering technology used to
create genetically modified foods.
2. The learner will be able to compare and contrast the benefits and potential risks of genetically
modified organisms.
Model 1
10 minutes
1. Using the information provided in model 1, what types of plants can be genetically modified using
gene splicing?
2. What is gene splicing?
3. Name the “source organism” that is providing the gene for this genetic engineering example.
4. What is the name of the desired bacterial gene, and what property of this gene is of interest to
agricultural scientists?
5. Why do you think genetic engineers would want to create Bt transgenic corn and cotton?
Model 2
10 minutes
1. Examine the graph shown in Model 2. What genetically engineered crop is most widely grown in the
U.S.?
2. According to the graph, when were genetically modified food crops adopted by the U.S.?
3. In the year 2007, what percentage of U.S. land acres were used to grow Bt cotton?
4. Make a prediction: If the graph were to show data from 2007 – 2011, would you expect GMO’s in
the form of food crops to increase or decrease? Support your answer with a brief explanation.
5. GM foods are genetically engineered for a specific purpose or attribute (desired characteristic). Use
Table 1 to list four reasons why crops are genetically modified.
Model 3
5 minutes
Study the diagram showing a piece of bacterial DNA that is resistant to cold temperatures being spliced
into a strawberry plant’s DNA. Arrange the diagrams in order by writing the letters A (first) through D
(last) in the spaces provided.
5. What would be an advantage of splicing a naturally-occurring cold-resistant bacterial gene into a
strawberry plant?
Model 4
20 minutes
Genetically Modified Food: The Benefits and the Risks
Genetically modified foods or GM foods for short, also go under many different names, including
transgenic food, genetically engineered food or biotech food.
So what are GM foods? Although different people and groups have different definitions, GM foods can
broadly define as foods that "are produced from crops whose genetic makeup has been altered through
a process called recombinant DNA, or gene splicing, to give the plant a desirable trait." The
modification is usually done in the lab using molecular techniques or genetic engineering although
there are others who would argue that crops produced through conventional breeding can also be
considered as GM food.
The first GM food crop, a tomato developed by Montsanto was submitted for approval to the US FDA in
August 1994 and came into market in the same year. As of September 9, 2008, a total of 111
bioengineered food products have completed the US FDA "consultation procedures" on bioengineered
foods. In addition to the tomato, the range of products includes soybean, corn, cotton, potato, flax,
canola, squash, papaya, radicchio, sugar beet, rice, cantaloupe, and wheat. According to estimates by
the Grocery Manufacturers of America, "between 70 percent and 75 percent of all processed foods
available in U.S. grocery stores may contain ingredients from genetically engineered plants. Breads,
cereal, frozen pizzas, hot dogs and soda are just a few of them."
The benefits of GM foods: Support for GM foods come from different sectors: scientists, economists,
and understandably from the agricultural and food industries.
1. GM foods can fight world hunger. The world population has reached an all-time high of over 6
and a half billion. Over 20% of these are suffering from poverty and hunger. That GM foods can
stop hunger is one of the noblest motivations behind the development of GM foods. GM foods
supposedly are easier to grow and bring higher yields.
2. GM crops are better. GM crops are designed to be sturdier and more robust than their nonmodified cousins. They are meant to be resistant to drought, diseases, and pests.
3. GM foods can fight malnutrition. In a world suffering from malnutrition, GM foods can answer the
need for more nutritious food. To cite an example, Swiss research strove to create rice strains
that contain large amounts of beta-carotene and iron to counteract vitamin A and iron deficiency.
Malnutrition can refer to both under-nutrition and wrong nutrition.
4. GM foods are good for the environment. GM foods translate into less use of pesticides,
herbicides and fertilizers, and therefore less pollution.
5. GM foods are safe. The FDA ensures that foods made from these plants are safe for humans
and animals to eat, the USDA makes sure the plants are safe to grow, and the EPA ensures that
pesticides introduced into the plants are safe for human and animal consumption and for the
environment.
The issues against GM foods:
1. GM foods are for profit. According to its opponents, GM foods were created for profit and nothing
else.
2. GM foods are unregulated. The use of GM foods in the world is almost an unregulated free-forall activity. Going through the US FDA consultation procedures is mainly voluntary.
3. There are also reports of GM plants escaping field trials and finding their way to the natural
environment, thousands of miles away. In 2006, rice which contained genes from the bacteria
Bacillus thuringiensis (the notorious Bt) found its way to European supermarkets, causing a big
outcry. The bacterial gene rendered the rice resistant to insects and the transgenic rice was a
test plant that has not yet been approved for human consumption.
4. GM foods can harm the environment. GM foods are affecting their environment and some of
these effects might actually be harmful. The effects are especially evident in other living
organisms within the vicinity. There are concerns, for examples, how cross-pollination with
pollens from GM plants can affect non-GM plants.
5. GM foods can be detrimental to human health. The main concerns about adverse effects of GM
foods on health are the transfer of antibiotic resistance, toxicity and allergenicity. With genetic
modifications come new compounds in the crops which we virtually know nothing about.
Your Opinion: Are you for or against genetically modified food? Write a 5 paragraph argumentative
essay in Google Docs stating your position on genetically modified foods citing 3 facts from the article
that support your opinion. Each paragraph should be no less than 4 sentences. The essay should be
written in the following format:
1) Paragraph 1: Introduction Paragraph including your thesis statement of opinion and summarizing the
3 facts that support your opinion.
2) Paragraph 2: Develop & Describe Fact #1
3) Paragraph 3: Develop & Describe Fact #2
4) Paragraph 4: Develop & Describe Fact # 3
Each paragraph should have a topic
sentence that clearly states the
subject of the paragraph; two to three
supporting sentences developing your
opinion on that subject; and a
conclusion sentence
5) Paragraph 5: Conclusion Paragraph includes a restatement of your overall opinion and summary of
the 3 facts supporting your opinion.