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Chapter 9Biotechnology

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Biotechnology0Biotechnology – the application of a technological

process, invention, or method to living organisms.

0Why would we want to extract DNA?

0How do you think we can remove DNA from a cell?

DNA Extraction video

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DNA Extraction0Use chemicals to break down cell membrane/wall and

nucleus.0The DNA is now free to be extracted

0DNA is sticky, and can be easily pulled out of a mixture. 0This is called “spooling” DNA

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Restriction Enzymes0After DNA has been extracted, restriction enzymes are added0Cut DNA at VERY SPECIFIC sites

0 Specific nucleotide sequence0 Makes large DNA molecules more manageable and easier to study. 0 Cuts it up into smaller sections.

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Restriction enzymes

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Gel electrophoresis0After the DNA is cut into

smaller, more manageable pieces, a gel electrophoresis technique is used.

0Gel electrophoresis uses an electrical current to separate a mixture of DNA fragments from each other. 0DNA is inserted into tiny

openings known as wells on the gel.

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Gel electrophoresis0DNA is negatively charged

because of the phosphate group in the nucleotide.

0Positive and negative charges attract therefore DNA moves towards positive end of gel.

0The DNA fragments are then sorted by size as they travel down the gel creating bands.

0The smaller the fragment, the further it moves down the gel.

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Gel electrophoresis

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Gel Electrophoresis

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Gel Electrophoresis0 This technique is also known

as “DNA Fingerprinting”0There is a 1 in 5.4million

chance that someone could have the same DNA as you.

0What are some of the ways that we use DNA fingerprinting today?

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Cloning0A clone is a genetically identical copy of a gene or an

organism0Asexual Reproduction = 100% identical0Example: Plants clone themselves0Example: Bacteria and binary fission = split into 2 0Example: Sea star re-growing lost limbs

(regeneration)0Jurassic Park Clip0The Island Clip

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CloningCloning “Dolly” 19971. A body cell is taken from a

donor who is going to be cloned.2. An unfertilized egg is taken from another individual and the nucleus is removed.3. The nucleus of the body cell is fused with the unnucleated egg cell to create an embryo.4. The embryo is then stimulated to begin dividing. 5. Embryo is implanted into a surrogate mother.0Dolly video0Cloning video

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Positive and negative of cloning.

Positive Negative

0organs for transplant into humans

0 save endangered species

0Higher crop yields

0 Cloning raises concerns.

0 low success rate0 clones “imperfect”

and less healthy than original animal

0 decreased biodiversity

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Why aren't the cloned cats exactly identical?

0Environment has an affect on gene expression

0Why?

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Genetic Engineering0Genetic Engineering – Changing an organism’s

DNA by inserting a foreign gene from one organism into another.0Uses a technique known as Recombinant DNA. 0 Recombinant DNA is DNA that contains genes

from more than one organism.0Bacteria are commonly used in recombinant

DNA.0Bacteria contain plasmids that are necessary

for genetic engineering.

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Transgenic/Recombinant DNA

0Plasmid – tiny rings of DNA found in bacteria

0Recombinant DNA results in a transgenic organism – an organism that has one or more genes from another organism inserted into its genome. 0Genetically modified organism (GMO)

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Transgenic organisms:Genetically engineered crops

- PROS: Resistant to frost, disease and insects0 Smaller amount of pesticides needed to protect plant0More and bigger plants produced

- CONS: Could cause health effects (allergic reactions, unknown side-effects)0Could affect pollinators0Decrease biodiversity0Lead to interbreeding among plants forming a hybrid

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Human Genome Project0Started in 1990, completed in 20030Research effort to sequence all of human DNA 046 chromosomes

0Over 3.3 billion nucleotides0Mapping every gene location (loci)0Conducted by scientists around the world

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Gene Therapy0The replacement of a defective or missing gene, or the

replacement of a new gene, into a person’s genome to treat a disease.

0First successful gene therapy took place in 19900Much of gene therapy is still experimental0Researchers are studying many different methods to treat

cancer0 Gene to stimulate persons immune system to attack cancer cells0 Insert “suicide” gene into cancer cells.