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Gourmet Genes - Lesson 1
Part1 - Part
2 - Part3 - Part4
If food already grows everywhere food can grow
- how can we grow even more?
Objectives
By the end of this lesson, students will be able to:
- Work as a team, and participate in peer review
- Compare and select alternative methods of applying
recombinant DNA to crops
- Understand techniques used in genetic engineering
- Explain how genes can be altered
- Understand gene-transfer techniques
- Understand how new biotechnology products are developed
Background Notes
For thousands of years, farmers and plant breeders have
saved the seed from, or bred, the largest and strongest
plants that appeared the least susceptible to disease.
They did not know it, but they were practicing a rudimentary
form of genetic engineering - a fundamental process used
in biotechnology.
About 150 years ago, Gregor Mendel began studying inheritance in garden plants
and discovered the rules governing the transmission of genetic characteristics.
By the 1980s, scientist had learned how to move these genes, or pieces of genetic
information, from one organism to another. Although still a relatively young
science, biotechnology holds tremendous promise for agriculture - enabling researchers
to develop improved crop plants, such as crops naturally protected from disease
and insects.
Materials
- Handouts of Activity Sheets A, B, and C for each student
- A "Gourmet Gene Award," to recognize the most creative team (optional)
Strategy
1. Hand out copies of Activity Sheet A, and let a volunteer read it aloud. Make
sure students understand the term recombinant DNA (involves cutting DNA with
restriction enzymes and putting it together again in a new arrangement), the
use of restriction enzymes (they work like scissors), and the process of altering
genes.
2. Divide students into teams of two or three or let them work alone. Hand out
copies of Activity Sheet B. Ask students to write a recipe for a new product
following the steps on the activity sheet. Remind them to use the correct process
for recombining DNA
3. You may require students to research recombinant DNA and genetic engineering
before they write their recipes. Transferring genetic information from one organism
to another is a complicated process. Traits, such as tolerance to drought, require
codes containing multiple genes and are difficult to confer on an organism. Students
should understand that they will be looking at the process in a simplified manner
using this activity
4. Let students know that their recipe will be peer-reviewed. Everyone gets a
chance to grade - or score - the results. Explain that peer review is an important
concept in accepting new scientific discoveries. A total of 100 points is available
for the recipes. Write the following on a chalkboard or flip chart:
- 25 points for creativity or uniqueness
- 25 points for technical accuracy
- 25 points for usefulness of product
- 25 points for recipe wording and ease of use
5. Give the students sufficient time to create and finish their recipes. Then
have them present their recipes to the rest of the group. You may ask some of
the following important questions:
- Do you think your recipe could be successfully developed? Could it be done
today?
- How important, on a scale of one to 10, is your new product? Why?
- What would be the cost of your new product?
- Think about the problem your crop faces. Is there a way to solve the problem
without using genetic engineering? Can you suggest an example?
6. Give students a few moments after each presentation to record a score. After
all have presented, collect the scores, average them, and announce or present
the "Gourmet Gene Award" to the team with the highest score.
7. Hand out copies of Activity Sheet C, and review the information. The sheet
describes the steps it takes to bring a genetically engineered crop to market.
This process can take years!
Source for lesson plan: Field of Genes: Making Sense of Biotechnology in
Agriculture, 4H, 1997.
Follow-Up Activities for Students
- Break the students into groups, and ask them to develop creative ways to
demonstrate recombinant DNA technology or genetically altered plant development.
One example would be "acting out" the process with "characters" being restriction
enzymes, genes, etc.
- Create a "film strip" on paper that demonstrates the steps of recombinant
DNA in a muddled order. Have students cut and paste the sections of the film
strip to put them in the right order. Ask them to use the appropriate "vocabulary
terms" to describe the process.
Additional Resources
Biotechnology Industry Organization
165 K Street, NW
Washington, DC 20006
(202) 857-0244
(202) 857-0237 fax
International Food Information Council
1100 Connecticut Avenue, NW, Suite 340
Washington, DC 20036
(202) 296-6540
(202) 296-6547 fax
National 4H Council
7100 Connecticut Avenue
Chevy Chase, MD
(301) 961-280
www.fourhcouncil.edu
Fields of Genes Making Sense of Biotechnology in Agriculture ($5.00/copy)
National Future Farmers of America Foundation
(703) 360-3600
www.ffa.agriculture.com/foundation/index.html
Saint Louis Mathematics and Science Education Center
316 Clark Hall
University of Missouri - St. Louis
8001 Natural Bridge Road
St. Louis, MO 63121
(314) 516-5650
Zero Population Growth, Inc.
1400 16th Street, NW, Suite 320
Washington, DC 20036
(202) 332-2200
World Population video ($19.95/copy)
Gourmet Genes: Activity Sheet A
Let's say you and your friends are making a videotape to send into a television
show. You're taping segments of people skiing down "Suicide Hill." Many people
fall. Others swoosh gracefully to the bottom. You'd like to put together a tape
of people falling, one right after the other. How could you do this?
Well, you could cut and splice.
Now, suppose you have a potato plant. You know that it's hardy and could be used
to grow crops that you could sell to the market. The only problem is that the
plant is often attacked by beetles. If there was a way to keep the beetles from
munching the plant, you could grow more potatoes. A friend of yours suggests
you take a gene from a bacterium that kills beetles, place it in the genetic
material of the potato plant, then cross this plant with similarly altered plants.
Voilà! You'd have a beetle-resistant plant. Well, it's not that simple,
but is it science fiction? No, it's recombinant DNA.
Putting DNA together in different combinations = Recombinant DNA
Recipe for Recombinant DNA
- DNA
- Restriction Enzymes
- Plasmid (ring of DNA found in some bacteria)
- Enzymes
- Bacterium
Use the restriction enzymes to cut apart the DNA. They are just like scissors.
Take a clean plasmid. Add some enzymes to "glue" the plasmid and DNA together.
Insert this mixture into a bacterium. When the bacterium reproduces, it will
copy the new DNA. Soon you will have many bacteria, each containing a copy of
the modified DNA.
Gourmet Genes: Activity Sheet B
Now that you understand what recombinant DNA is, come up with your own recipe.
Start by picking a crop. The box at the bottom suggests some crops along with
the problems they face.
My crop is:
Next, cite a problem it faces:
Now, think: Is there something in nature that is not bothered by the same thing?
Does it have a natural immunity? For example, is there a plant or other organism
not bothered by freezing temperatures? What is it?
Now, write your recipe for a new and improved crop.
Recipe Name:
Ingredients:
Directions:
Crop |
Problem |
Corn |
Corn borer (insect) |
Wheat |
Rust (fungal
disease) |
Tomatoes |
Fungal disease |
Grapefruit |
Can't grow in
climates that freeze |
Potatoes |
Colorado potato
beetle |
Rice |
Low in Vitamin
E |
Strawberry |
Berries can't
survive hard freeze |
How else might you deal with the problem you chose? Other tools available that
might help manage your problems, either combined with or instead of genetic engineering,
include:
- Using some helpful insects to control other insects
- Growing different crops in different years to
control pests and diseases
- Conventional selective breeding for the trait
of interest, like resistance to diseases or insects, or for increased amounts
of vitamins
- Using pesticides to control diseases or insects
Genetic Engineering is one tool among
many used in agriculture.
Gourmet Genes: Activity Sheet C
How New Plants Get Developed
In real life, it's not that easy to develop a new genetically engineered plant.
Scientists must go through many years of testing before they bring a new crop
to the market. Here are the real steps it takes to develop a new type of plant
using biotechnology.
How New Plants Get Developed: Steps to Development
1. Identify the trait you want.
2. Identify the source of the gene.
3. Isolate the gene from that source.
4. Adjust the gene to confer the desired trait.
5. Transfer the gene to the plant.
6. Test to see if the trait you wanted is there.
7. If it is, go to step 8. If it isn't, go back to step 5.
8. Run field trials to make sure:
a) There are no detrimental effects of the gene
b) The gene works the way you want it to work
9. At the same time you run the field trials, do initial product safety trials.
10. Submit information as required to regulatory agencies.
11. You're now in the regulation loop.
Continue
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