genetically modified organisms (gmos) learning target: 1

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Genetically Modified Organisms (GMOs)

Learning Target:

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Genetic EngineeringI Can… Describe, in general terms, how

the genetic information of an organism can be altered to give the organism new genetically based traits. I Will…• List examples of cloning of organisms

occurring in nature.• Briefly describe the steps of Somatic

Cell Nuclear Transfer (SCNT) in cloning mammals

• Connect the structure of DNA and process of protein synthesis with reasons why genetic engineering is possible.

• List the steps necessary to produce a transgenic organism

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Genetic EngineeringKEY CONCEPT:

• DNA sequences of organisms can be changed.• Entire organisms can be cloned• New genes can be added to an

organism’s DNA• Genetic engineering produces

organisms with new traits

Principles of genetics and cellular chemistry can be used to produce new foods and medicines in biotechnological processes.

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• Plants • Clone themselves from roots, stems and leaves• Plant tissue contains many stem cells that can develop into many types of cells

Clone:• genetically identical copy of a gene or an organism

Cloning occurs in nature:

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Bacteria:• Clone themselves during asexual reproduction through binary fission

Cloning occurs in nature:

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Simple Animals:• Clone themselves during asexual reproduction through budding e.g. Hydra• Clone themselves during regeneration e.g. sea star

Cloning occurs in nature:

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Cloning mammals – more difficult

Somatic Cell Nuclear Transfer (SCNT)• Haploid nucleus removed from

unfertilized egg gamete cell• Diploid nucleus from somatic cell

inserted into the egg cell• Stimulated (chemicals and

electricity) to go through mitosis and start dividing

• Embryonic bastocyst (mass of cells) implanted in uterus

• Develops into cloned offspring23 46

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First clone of an adult mammal:

• Dolly the sheep (1977)

• Many other mammals cloned

since

• Biotechnology

companies

clone beloved

pets

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Rainbow – Somatic cell DNA

CC – Cloned/Carbon Cat

Allie – Surrogate mom

Egg donor– Anonymous

Many Factors affect gene expression – Epistasis, Inactivation, Methylation, … • Epigenetics

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Cloning: ControversialPros

• Creation of personal stem cells

• Organ transplant

• Treat diseases

• Spinal cord injuries

• Save endangered species

Cons• Low success

rate• Expensive• Health issues

in clone• Reduces

biodiversity• Ethic of

“creating” life• When does

life begin?

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Genetic Engineering:• Changing and adding genes to

an organism’s DNA to give it new traits• Clones genes not whole

organisms

How and why can we do this?

DNA is UNIVERSAL!• DNA – 4 common nucleotides

(A,T,G,& C)• DNA – Common double helix

structure• RNA – Common 4 nucleotides (A, U,

G, & C)• Codons – code for 20 common amino

acids the make proteins

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Genetic engineering is based on:• Recombinant DNA• DNA that contains genes

from more than one organism• Engineer crops to be

resistant to cold or insects• Engineer crops to produce

vitamins or medicines• Engineer bacteria to

produce medicines or enzymes

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Bacterial plasmids are often used to make recombinant DNAPlasmid - closed loop of DNA in bacteria separate from the bacterial chromosome• Will

replicate on its own within the cell

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Transgenic organism - has one or more genes from another organism inserted into its genome Transgenic bacteria used to make human insulin:• Gene

inserted into plasmid

• Plasmid inserted into bacteria

• Bacteria expresses gene

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Transgenic plants are common in agriculture:

• Transgenic bacteria infect a plant

• Plant expresses foreign gene

• Many crops are now genetically modified (GM / GMO -organism)

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Scientists have concerns about some uses of genetic engineering:• Possible long-term health effects

of eating GM foods• Allergies• Diseases

• Possible effects of GM plants on ecosystem and biodiversity• Keystone species cascade

effect• New vulnerabilities of

engineered organismhttp://webertube.com/mediadetails.php?mid=8468&

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Genetically Modified Organisms (GMOs)

Learning Check :

List 4 reasons why genetic engineering is possible

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Learning Check :List 4 reasons why genetic engineering is possible

Name: ___________________

Name: ___________________

Name: ___________________

Name: ___________________

Learning Check :

Learning Check :

Learning Check :

List 4 reasons why genetic engineering is possible

List 4 reasons why genetic engineering is possible

List 4 reasons why genetic engineering is possible