Genetically modified (GM) organisms - science-b

neighgreasycornerBiotechnology

Dec 14, 2012 (5 years and 23 days ago)

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© 2011 Pearson Education, Inc.

Pests and Pollinators

&

Genetically Modified Food

AP Environmental
Science

Mr. Grant

Lesson
62

© 2011 Pearson Education, Inc.

Objectives:


Define
the term
seed banks
.


Discuss
the importance of pollination.


Describe
the science behind genetically modified food.


Evaluate
the debate over genetically modified food.


TED
-

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
food
-
crop for whatever tomorrow may bring.

© 2011 Pearson Education, Inc.

Seed
Bank
: Place
where seeds are stored for
short
-
term use in farming or for long
-
term
preservation.

Define
the term
seed banks
.

© 2011 Pearson Education, Inc.

Discuss
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.

© 2011 Pearson Education, Inc.

We depend on insects to pollinate crops


Not all insects are pests; some are absolutely vital

-
800 crop species rely on insect pollinators


Pollination

= male plant sex cells fertilize female sex
cells

-
By wind or animals


Pollinators include:

-
Hummingbirds

-
Bats

-
Insects (bees, wasps, etc.)

Flowers are evolutionary adaptations to attract pollinators

© 2011 Pearson Education, Inc.

Conservation of pollinators is vital


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


Colony collapse disorder = entire beehives have
vanished

-
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
services/year

© 2011 Pearson Education, Inc.

Describe
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

= organisms that
have been genetically
engineered by …


Recombinant DNA

= DNA
created from multiple
organisms

© 2011 Pearson Education, Inc.

Biotechnology is impacting our lives


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



Transgenic organism

= an organism that contains DNA
from another species

-
Transgenes
=

the genes that have moved between
organisms


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

© 2011 Pearson Education, Inc.

Some genetically modified foods

© 2011 Pearson Education, Inc.

Genetic engineering versus agricultural
breeding


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

© 2011 Pearson Education, Inc.

Biotechnology is changing our world


GM foods are a big business


Most GM crops are herbicide
and pesticide resistant

-
Large
-
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

© 2011 Pearson Education, Inc.

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
plants

© 2011 Pearson Education, Inc.

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

© 2011 Pearson Education, Inc.

Evaluate
the debate over genetically modified
food.


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.

© 2011 Pearson Education, Inc.

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

© 2011 Pearson Education, Inc.

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
investments

© 2011 Pearson Education, Inc.

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


The
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

© 2011 Pearson Education, Inc.

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
(17:06)