Plant Cell Structure and Function through Visual Slides

Genetically Modified Food

What is Genetic Modification?

To “modify” means to change, so

genetic modification is the

change of the genetic code

(DNA) of an organism.

Genetically modified plants are

referred to as “GM plants”.

History of GM plants

•

In 1994, the first GM was introduced to the

American market without special labels

–

The product was FlavrSavr, a tomato that was more

resistant to rot. This allowed it to ripen on the vine,

giving it improved taste.

–

FlavrSavr was taken off the market in 1997 due to

high production costs and low profits.

•

After FlavrSavr, other companies began

increasing production of GM crops

How do they do it?

Scientists called biotechnologists find a trait in one organism

that they would like for a plant to have. They search the

DNA of the organism until they find the genes that control

the desired trait, then they introduce the genes into the

plant’s DNA. This causes the plant to express the traits

controlled by the genes it received from the other organism.

Plant Cell

How common are GM plants?

•

Many people are surprised to find out that GM

plants are very common in the U.S.

•

Main GM crops in the U.S.:

–

Soybeans: 93%

–

Cotton: 93%

–

Corn: 86%

•

The U.S. produces about 68% of the world’s GM

crops

–

Many other countries are more resistant to GM

technologies

Why Modify?

Genes inserted into plant DNA

can make plants resistant to

herbicides, pesticides,

viruses, and even cold

weather.

Other types of genes can make

plants more nutritious or

help them stay ripe longer.

Controversy

If GM plants are resistant to pesticides

and herbicides, have longer shelf life,

and can be more nutritious, why are so

many people against them?

Are GM foods bad for your health?

•

GM foods do not require special testing or special

labels at this point in time.

–

Some research shows that GM foods cause damage

to the organs of mice and other animals.

–

Other research shows that GM foods do not cause

any damage to animals.

–

It is tricky to test the effects of GM food on animals,

and researchers get different results depending on

what methods they use.

•

If we can’t test it properly, then how can we be sure it’s safe?

Effects on the Environment

•

Many plants rely on the wind for pollination, and

pollen from a GM crop can be blown onto non-

altered crops.

–

Since you can’t control the wind, it is not yet possible to

prevent accidental cross pollination. Organic crops could

become accidental GM crops.

•

Some are concerned that the GM plants may even

cross with plants in the wild, causing changes in the

food chain.

–

If an animal relies on a certain plant, and then the plant

changes, will the animal be able to survive?

–

Will these altered genes be transferred

to animals?

The Farmers

•

Many farms save the seeds from the best plants to start

the next year’s crop. The biotech companies require

farmers to buy new seed every year so they can continue

to make money.

–

This makes farming more expensive for the farmers who

rely on their crops to make a living.

–

Monsanto, a top GM seed producer, has even taken

farmers to court for saving seeds instead of buying new

ones.

–

Terminator Technology causes the seeds produced by

some GM plants to be sterile, which insures that farmers

cannot save any seed.

Is it okay to tamper with nature?

•

Modification is not a new idea. In nature, new

genes are constantly being created and spread

through the population.

–

The main differences between natural selection

and genetic modification:

•

Technology is used to pick specific genes instead of

new genes spreading by chance

•

We can now insert genes from one organism into a

completely different organism

Conflicting Information

•

It is hard to find unbiased information about

genetic modification

–

Biotech companies do not want to release any

negative data that would cause their sales to drop

–

Anti-modification groups are bound and determined

to release the most negative data to convince people

to be on their side

–

You have to use good judgment to decide whether

modification is “right” or “wrong”

What do YOU think?

Helpful Websites

•

General information

–

http://tiki.oneworld.net/genetics/home.html

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http://www.who.int/foodsafety/publications/biotech/20questio

ns/en/

•

Anti-Modification

–

http://www.saynotogmos.org/

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http://www.greenpeace.org/international/en/campaigns/agricu

lture/problem/genetic-engineering/