Genetically modified (GM) organisms - science-b


14 déc. 2012 (il y a 9 années et 1 mois)

361 vue(s)

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Pests and Pollinators


Genetically Modified Food

AP Environmental

Mr. Grant


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the term
seed banks

the importance of pollination.

the science behind genetically modified food.

the debate over genetically modified food.


The varieties of wheat, corn and rice we grow today
may not thrive in a future threatened by climate change. Cary
Fowler takes us inside a vast global seed bank, buried within a
frozen mountain in Norway, that stores a diverse group of
crop for whatever tomorrow may bring.

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: Place
where seeds are stored for
term use in farming or for long

the term
seed banks

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the importance of pollination.

Insects and other organisms are essential for the
reproduction of many crop plants.

Conservation of pollinating insects is vitally important
to our food security.

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We depend on insects to pollinate crops

Not all insects are pests; some are absolutely vital

800 crop species rely on insect pollinators


= male plant sex cells fertilize female sex

By wind or animals

Pollinators include:



Insects (bees, wasps, etc.)

Flowers are evolutionary adaptations to attract pollinators

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Conservation of pollinators is vital

Populations of pollinators (e.g., bees) have plummeted

Colony collapse disorder = entire beehives have

Unknown causes

Insecticides? Parasites? Stress?

Reducing or eliminating pesticide use and planting
flowering plants will help preserve bees

Bees pollinate over 100 crops
and contribute $15 billion in

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the science behind genetically
modified food.

Genetic modification uses recombinant DNA
technology to move genes for desirable traits from one
type of organism to another.

Genetic engineering is both like and unlike traditional
selective breeding.

GM crops may have ecological impacts, including the
spread of transgenes, an increase in chemical pollution,
and indirect impacts on biodiversity.

© 2011 Pearson Education, Inc.

Genetically modified organisms

Genetic engineering

laboratory manipulation of
genetic material

Add, delete, modify DNA

Genetically modified (GM)

= organisms that
have been genetically
engineered by …

Recombinant DNA

created from multiple

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Biotechnology is impacting our lives

= the application of biological science to
create products derived from organisms

Transgenic organism

= an organism that contains DNA
from another species


the genes that have moved between

Biotechnology has created medicines, cleaned up
pollution, and dissolved blood clots

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Some genetically modified foods

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Genetic engineering versus agricultural

Traditional breeding = changes organisms through
selective breeding of the same or similar species

Works with organisms in the field

Genes come together on their own

Uses the process of selection

Genetic engineering = mixes genes of different species

Works with genetic material in the lab

Directly creates novel combinations of genes

Resembles the process of mutation

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Biotechnology is changing our world

GM foods are a big business

Most GM crops are herbicide
and pesticide resistant

scale farmers grow
crops more efficiently

Most U.S. corn, soybeans,
cotton, and canola are
genetically modified

Globally, 14 million farmers grew GM foods on 134
million ha

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What are the impacts of GM crops?

As GM crops expanded, scientists, citizens, and
policymakers became concerned

Impacts on human health

Concerns over escaping transgenes

They could harm nontarget organisms

Pests could evolve resistance

They could ruin the integrity of native ancestral
races and interbreed with closely related wild

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Genetic engineering has benefits and risks

Environmental benefits of genetic engineering:

Reduced use of chemical insecticides

Increased no
till farming

Decreased irrigation, deforestation, land conversion

Negatives of genetic engineering:

Increased herbicide use affects health and habitats

Some GM fields support less biodiversity

Precautionary principle
= don’t undertake a new
action until the effects of that action are understood

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the debate over genetically modified

Many people have ethical qualms about altering food
through genetic engineering.

Opponents of GM foods view multinational
biotechnology corporations as a threat to the
independence of small farmers.

Nations have adopted differing stances on GM foods.

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The GM debate involves ethics

People don’t like “tinkering” with the food supply

With increasing use, people are forced to use GM
products, or go to special effort to avoid them

Multinational corporations threaten the small farmer

Research is funded by corporations that profit if GM
foods are approved for use

GM crops have not eradicated hunger

GM crops do not focus on increased nutrition,
drought tolerance, etc.

The GM industry is driven by market considerations
driven by financial interests of corporations

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GMO producers are suing farmers

Monsanto has launched 112 lawsuits against 372
farmers, winning an average $385,000 per case

Monsanto sued Percy Schmeiser of Canada for
using its GM seeds without paying for them

Schmeiser said the seeds blew onto his field from
adjacent fields

The courts sided with Monsanto, saying that
Schmeiser had violated Monsanto’s patent

Corporations go to great lengths to protect their GM

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The future of GM foods

Europeans demand that GM foods are labeled

U.S. consumers have mostly accepted GM crops

They don’t realize most food contains GM products

The U.S. sued the European Union before the World
Trade Organization for hindering free trade

Cartagena Protocol on Biosafety
lays out
guidelines for open information about exported crops

The U.S. has not joined

Brazil, India, and China approve GM crops

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TED Video

Biodiversity warrior Cary Fowler wants
to save the world from agricultural
collapse, one seed at a time.

"For individual crop varieties, doomsday does come every day. We want
to put an end to that."

Cary Fowler: One seed at a time, protecting the future of food