Transcript 15.1_Selective_Breeding

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Review Give and example of selective breeding
Review what is the relationship between genetic
variations and mutations.
Explanation Write a paragraph in which you
suggest ways that plants could be genetically
altered to improve the world’s food supply
CH 15 GENETIC ENGINEERING
15.1 Selective Breeding
Selective Breeding
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Method of breeding where
the organisms that breed are
picked due to certain traits
People have done this for a
long time with many species
Native Americans selectively
bred teosinte to produce corn.
Hybridization
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Crossing dissimilar individuals to bring together the
best of both organisms
Individuals produced by such crosses are often
hardier than either of the parents
Can increase the disease resistance or increase
food production.
Inbreeding
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Continued breeding of individuals with similar
characteristics
Useful in preserving certain traits- dog breeds
Increases the chance that a cross between two
individuals will bring together two recessive alleles
for a genetic defect.
Biotechnology
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Application of a technological process, invention,
or method to living organisms.
Increasing Variation
Mutations
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Ultimate source of biological diversity
Occur spontaneously
Breeders can increase the mutation rate using
radiation or chemicals
Used often with bacteria.
Polyploid Plants
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Given drugs to prevent chromosomes from
separating
Often are larger and stronger.