Download GMOs - CIA-Biology-2011-2012

Artificial Selection
Exploring Biotechnology & GMOs
What is Artificial
Selection?
What words come to
mind when you think
of Artificial Selection?
What is Artificial
Selection?
 A process in which humans consciously select for
or against particular features in organisms.
 For example, humans may select only organisms
with a desired feature to reproduce or provide more
resources to the organisms with the desired feature.
 This process causes evolutionary change in the
organism and is similar to natural selection only
with humans, not nature, doing the selecting.
AS Example:
 Pigs are artificially selected
by man to produce the
largest amount of meat
AS Example:
 Animal breeders
 Peed in racehorses, milk production in cows, trail
scenting in dogs.
 Over the years, the plants with desirable characteristics
are grown by man and their numbers increase.
Meanwhile, plants without these characteristics are less
likely to survive as they are not provided with the
fertilizers and pesticides by man.
 Eventually, the species of the plant will evolute.
 What may be an example of this?
GMOs &Artificial Selection
 GMOs: Genetically Modified Organisms
 Crop plants created for human or animal
consumption using the latest molecular biology
techniques.
 Biotechnology: Application of scientific and
technical advances in life science to develop
commercial products
How to create GMOs
 Traditionally: breeding
 time consuming
 often not very accurate
How to create GMOs
 GENETIC ENGINEERING
 Create plants with the exact desired trait very
rapidly and with great accuracy.
 For example: plant geneticists can isolate a gene
responsible for drought tolerance and insert that
gene into a different plant. The new geneticallymodified plant will gain drought tolerance as well.
Did you know?
 Genes can be transferred from one plant to another
and from non-plant organisms.
 The best known example is the use of B.t. genes in
corn and other crops.
 B.t., or Bacillus thuringiensis, natural bacterium that
produces crystal proteins that are transferred into
corn  self produce pesticides
Let’s engineer our own
crop
 http://www.pbs.org/wgbh/harvest/engineer/tran
sgen.html
How prevalent are GM
crops?
 Thirteen countries grew genetically-engineered
crops commercially in over a decade, the U.S.
produced the majority.
 68% of all GM crops were grown by U.S. farmers. In
comparison, Argentina (23%), Canada (7%) and
China produced (1%).
 Other countries that grew commercial GM crops:
Australia, Bulgaria, France, Germany, Mexico,
Romania, South Africa, Spain, and Uruguay.
How prevalent are GM
crops?
 40 plant varieties commercialized by the
government including: tomatoes, cantalopes,
soybeans
 Not all these products are available in supermarkets
yet the prevalence of GM foods in U.S. grocery
stores is more widespread
 Highly processed foods and its ingredients mixed
with genetically modified ingredients
What are some advantages
of GM Foods?
 Pest resistance/Herbicide tolerance/ Disease
resistance
 Cold tolerance/Drought tolerance/salinity
tolerance
 Reduced Maturation time
 Nutrition
 Pharmaceuticals
 Phytoremediation
What are some criticisms
against GM foods?
Environmental hazards
 Unintended harm to other organisms
 Reduced effectiveness of pesticides
 Gene transfer to non target species
Human health risks
 Allergenicity
 Unknown effects on human health
Economic concerns
What’s your stance?
 Selective breeding of agricultural crops can benefit
populations in less-developed countries by
producing hardier crops, increasing food supplies,
and improving the nutritional content of food.
However, opponents of artificial selection
technology believe that it affects the natural ability
of a species to reproduce, which negatively affects
biodiversity.
What’s your stance
 Brainstorm with your group key points for your argument
 Support your points with facts and examples
 Try this: Vote Online - Should we grow GM crops?
 Debate next class!
Food for thought
 Genetically-modified foods: Good or bad?
 solve many of the world's hunger and malnutrition
problems
 help protect and preserve the environment
 Proceed with caution to avoid causing unintended
harm to human health and the environment.