13–2 Manipulating DNA

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132 Manipulating DNA

• A. The Tools of Molecular Biology
• DNA Extraction
• Homogenization Cell walls, membranes, and
  nuclear material are broken
• Emulsification Soap and enzymes break down
  membranes and emulsify lipids and proteins.
• Precipitation Alcohol is layered on top of the
  solution. DNA is not soluble in alcohol and
  precipitates either in the alcohol or at the
  interface between the alcohol and the rest of the
  mixture.
• Collection DNA can be pulled up from the
  interface or alcohol with a paper clip or glass
  rod.

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132 Manipulating DNA

• Cutting DNA
• Restriction Enzymes
• Cut DNA at precise locations,
• Cut a specific sequence of nucleotides

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132 Manipulating DNA

• Cutting DNA Restriction Enzymes
• Cut DNA at precise locations, Cut a specific
  sequence of nucleotides

Recognition sequences
DNA sequence
Restriction enzyme EcoRI cuts the DNA into
fragments.
Sticky end
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132 Manipulating DNA

• Cutting DNA Restriction Enzymes
• Cut DNA at precise locations, Cut a specific
  sequence of nucleotides

Recognition sequences
DNA sequence
Restriction enzyme EcoRI cuts the DNA into
fragments.
Sticky end
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132 Manipulating DNA

• 3. Separating DNA

DNA plus restriction enzyme
Power source
Longer fragments
Shorter fragments
Mixture of DNA fragments
Gel Electrophoresis
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132 Manipulating DNA

• B. Using the DNA Sequence
• 1. Reading the Sequence
• 2. Cutting and Pasting
• 3. Making Copies

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132 Manipulating DNA

• B. Using the DNA Sequence
• 1. Reading the Sequence
• 2. Cutting and Pasting
• 3. Making Copies

p324
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132 Manipulating DNA

• B. Using the DNA Sequence
• 1. Reading the Sequence
• 2. Cutting and Pasting
• 3. Making Copies

DNA polymerase adds complementary strand
DNA heated to separate strands
DNA fragment to be copied
p325
PCRcycles 1 DNAcopies 1
4 8
5 etc. 16 etc.
2 2
3 4
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132 Manipulating DNA

• B. Using the DNA Sequence
• 1. Reading the Sequence
• 2. Cutting and Pasting
• 3. Making Copies

DNA polymerase adds complementary strand
DNA heated to separate strands
DNA fragment to be copied
p325
PCRcycles 1 DNAcopies 1
4 8
5 etc. 16 etc.
2 2
3 4
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133 Cell Transformation

• Sneaking In
• You probably have heard of computer viruses. Once
  inside a computer, these programs follow their
  original instructions and override instructions
  already in the host computer. Scientists use
  small packages of DNA to sneak a new gene into
  a cell, much as a computer virus sneaks into a
  computer.

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133 Cell Transformation

• Sneaking In

1. Computer viruses enter a computer attached to
some other file. What are some ways that a file
can be added to a computers memory? 2. Why would
a person download a virus program? 3. If
scientists want to get some DNA into a cell, such
as a bacterial cell, to what sort of molecule
might they attach the DNA?
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CELL TRANSFORMATION
Essential Questions What happens during cell
transformation? How can you tell if a
transformation experiment has been successful?
In 13.2 we talked about manipulating DNA How do
we get it back into the cell? TRANSFORMATION- a
cell takes in DNA from outside the cell. The DNA
becomes part of the cells DNA REMEMBER -
Griffiths experiment
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TRANSFORMING BACTERIA
In 13.2 we talked about manipulating DNA.How do
we get it back into the cell? TRANSFORMATION- a
cell takes in DNA from outside the cell. That DNA
becomes part of the cells DNA REMEMBER -
Griffiths experiment
Transforming Bacteria Foreign DNA attached to
plasmid Plasmid - small circular piece of natural
DNA ensures DNA will be replicated contains
genetic marker such as resistance to
antibiotic (cells that survive antibiotic
have been transformed)
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Transforming Bacteria

• Plasmid - circular piece of bacterial DNA
• Recombinant DNA just has to be inserted into
  plasmid

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Transforming Bacteria

• Bacterial Transformation

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Bacterial Transformation
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Bacterial Transformation
Gene for human growth hormone
Section 13-3
Recombinant DNA
Gene for human growth hormone
Human Cell
Sticky ends
Bacterial chromosome
Plasmid
Go to Section
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Bacterial Transformation
Gene for human growth hormone
Section 13-3
Recombinant DNA
Gene for human growth hormone
Human Cell
Sticky ends
DNA insertion
Bacterial chromosome
Bacterial Cell
Bacterial cell for containing gene for human
growth hormone
Plasmid
Go to Section
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Transforming Bacteria Foreign DNA attached to
plasmid Plasmid - small circular piece of natural
DNA ensures DNA will be replicated contains
genetic marker such as resistance to antibiotic
(cells that survive antibiotic have been
transformed)
Transforming Plant Cells In nature, bacteria
insert plasmids into plant cells and produce
tumors Researchers disable tumor producing
gene and introduce foreign DNA Bacteria insert
the foreign DNA into the plant
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Transforming Plant Cells In nature bacteria
insert plasmid into plant cells that produces
tumors Researchers disable tumor producing
gene and introduce foreign DNA Bacteria insert
the foreign DNA into the plant
Sometimes possible to remove cell wall and have
plants take up DNA on their own If transformation
is successful, the foreign DNA is integrated into
one of the hosts chromosomes.
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If transformation is successful, the foreign DNA
is integrated into one of the hosts chromosomes.
Transforming Animal Cells Similar to
plants Sometimes possible to inject DNA into egg
cells Usually contain marker gene Recently
developed techniques enable genes to, knock out
host gene
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Transforming Animal Cells Similar to
plants Sometimes possible to inject DNA into egg
cells Usually contain marker gene Recently
developed techniques enable genes to, knock out
host gene
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13.4 Applications of Genetic Engineering What
are some examples of useful transgenic
organisms? What are the main steps involved in
cloning?
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What are some examples of useful transgenic
organisms? What are the main steps involved in
cloning?
Applications of Genetic Engineering In 13.2, we
learned how DNA is manipulated In 13.3, we
learned how foreign DNA is inserted into host
cells Does this work between animals and plants?
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In 13.2, we learned how DNA is manipulated In
13.3 we learned how foreign DNA is inserted into
host cells Does this work between animals and
plants?
Transgenic Organisms Contain genes from other
organisms Spurred growth of Biotechnology Transgen
ic Microorganisms Important products insulin
growth hormone Human genes inserted into bacteria
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Transgenic Microorganisms Important
products insulin growth hormone Human genes
inserted into bacteria
Transgenic Animals Mice given human genes to
study human immune system Livestock given genes
for extra growth hormone Poultry given genes to
resist infection
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Transgenic Animals Mice given human genes to
study human immune system Livestock given genes
for extra growth hormone Poultry given genes to
resist infection
Transgenic Plants Important part of food
production NOW 52 of soybeans 25of corn in
US Built-in insecticides Built-in weed control A
strain of rice with added vitamin A
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Transgenic Organisms
134 Applications of Genetic Engineering
Sometimes DNA directly injected Knockout genes
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A donor cell is taken from a sheeps udder.
Donor Nucleus
These two cells are fused using an electric shock.
Fused Cell
Egg Cell
The nucleus of the egg cell is removed.
An egg cell is taken from an adult female sheep.
The fused cell begins dividing normally.
Embryo
The embryo is placed in the uterus of a foster
mother.
Cloned Lamb
The embryo develops normally into a lambDolly
Foster Mother
Go to Section
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134 Applications of Genetic Engineering Cloning
A body cell is taken from a donor animal.
An egg cell is taken from a donor animal.
The nucleus is removed from the egg.
The body cell and egg are fused by electric shock.
The fused cell begins dividing, becoming an
embryo.
The embryo is implanted into the uterus of foster
mother.
The embryo develops into a cloned animal.
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134 Video Clone Age

• Copy these questions and use them to guide your
  note taking during the video
• What is a clone?
• Give some examples of plants and animals that
  have been cloned.
• The video claims that there are human clones
  walking among us. Explain how this could be true.
• Would a cloned human be the same as the human he
  or she was cloned from? Explain