Transcript PPT

Biotechnology
Selective Breeding
Humans have been breeding animals to
manipulate their DNA/Traits for many years!
Selective Breeding – humans only allow
animals with desired characteristics to breed and
produce offspring
Example – dogs bred to be “better hunters”, “better retrievers”
Biologists Manipulate DNA
• Scientists use biotechnology to perform
practical tasks & produce specific products
(medicines, etc.)
• Today, we manipulate the genomes
(DNA/Genes) of organisms like plants and
animals.
• Biotechnology – the process of
manipulating organisms, cells, or molecules
to produce specific products.
Recombinant DNA Technology
Technology where DNA and/or genes from different
sources are combined to change the genetic
composition of living organisms…even genes from
different species!
Recombinant DNA – DNA (made in a lab) that is then
attached to the DNA of another organism (thus
changing a specific characteristic of that
organism)
FYI - A Few Uses of DNA technology:
1. Make more “nutritious” crops (ex. Golden Rice)
2. Make medicine in large quantities (ex. Goats)
Bacteria – Common “Vector”
Bacteria are commonly worked with in
biotechnology because they can acquire
new genes in many ways and copy
DNA in large quantities!
3 Ways Bacteria can Acquire DNA:
1. Conjugation - “Tunnel” forms a
bridge between the bacteria
where DNA can travel.
2. Transformation – bacteria can
“take up” free floating DNA into
their own DNA
3. Use Plasmids 
Engineering Bacteria
• Bacteria contain plasmids
• Plasmids are small circular pieces of
DNA separate from the bacterial
chromosome.
• Carry cool genes (for awesome traits!)
Plasmids
Bacteria can transfer/swap plasmids to one another
and scientists can manipulate plasmids to make
them useful to us!!
Example:
1. Insert a gene (to make a medicine) into a plasmid
2. Put the plasmid into bacteria
3. When the bacteria reproduce they make many
copies of the gene & the medicine!
Desired Gene
1.
Cut
– Use restriction enzymes to
cut the desired DNA/gene out
of a larger chromosome
2.
Paste
– Put the desired DNA/gene
fragment into a plasmid
3.
Insert
- Put the plasmid into a bacterium
4.
Bacteria reproduce - making
many copies of the desired
gene!!
Useful Products Using Genetic
Engineering
1. Bacteria make chemicals that clean up hazardous
spills
2. Plants that are more nutritious (“golden rice”)
3. Cattle that can make insulin hormone in their milk
for people with diabetes
4. Goats make antibiotic to secrete in their milk
13.3 Genetically Modified
Organisms
• A genetically modified organism (GMO) is
any organism that has acquired any genes
artificially.
• If a species is called TRANSGENIC if it
has foreign genetic material from a
different species in it.
Genetically Modified Plants
Do you eat genetically modified
foods/plants??
YES
NO
Just a few…GMO FOODS
• Honey
• Cotton
• Tomatoes
• Corn
• Vegetable Oil
• Peas
• Potatoes
• Many cereals
Genetically Modified Plants
• Over 88% of soybean and 94% of corn crops
are genetically modified !
• Most common (GMO) genetic modifications:
– Genes for disease resistance
– Genes to resist insect and fungal pests
Genetically Modified Animals
• Goals for GMO animals…
– Produce mass quantities of medications (ex.
insulin)
– Get animals to market quicker (salmon)
– Breed animals with better quality products (sheep
wool)
– FUN!! $$$$$$$
Fincasters Episode 8
GloFish - YouTube
Few more
examples…
Genetically Modified
Salmon - Coming Soon? YouTube
• Transgenic Cows
The GMO Controversy
Although studies to date have shown that eating
genetically modified foods have no negative
health affects…people continue to demand
stricter regulations.
Major Concern:
GMO food can pose unknown health
risk…people are requesting strict labeling
laws!
**”ORGANIC CRAZE”**
GMO Controversy
Pros & Cons of GMO Foods
PROS
• Higher Yields (produce more)
CONS
• No “long term” studies to test
safety
• Use less land & energy
• Lower $ for consumers
• Insect resistant crops may hurt
helpful insects (such as bees)
• Insect resistant (need fewer
chemicals)
• Need more “weed-killing”
chemicals
• Studies conducted show no
negative health effects
• Costly patents can put smaller
farmers out of business
• Unknown allergy concerns
• Consumers don’t know what
exactly they are eating!
DNA Technologies & Their Uses
1.
2.
3.
4.
5.
Human Genome Project
PCR – Polymerase Chain Reaction
Gel Electrophoresis
Gene Therapy
Cloning
DNA Technologies
Human Genome Project (HGP)
An international scientific research project with the goal of
determining the sequence of chemical base pairs which
make up human DNA, and of identifying and mapping all of
the genes of the human genome from both a physical and
functional standpoint.
Started in 1990
Completed in 2003
Ethics - Genetic Ownership of Genes
DNA Technologies
FYI: Sometimes it is necessary to make many
copies of a piece of DNA from a single sample.
• PCR or Polymerase Chain Reaction
technique used to mass produce specific
sequences of DNA
Thermocycler
PCR Technique
“make a lot of DNA” from a small sample
Gel Electrophoresis!!!
• Technique used to separate and analyze
fragments of DNA.
• Produces “banding patterns” based on the
size of the DNA fragments as they move
through a gel due to electric current.
How it works!
DNA is cut into
“fragments” by
restriction enzymes
DNA “fragments” move
through gel using
electric current
Smaller DNA
fragments
move further
Online Gel Electrophoresis
Gel Electrophoresis Virtual Lab
DNA Fingerprint
• Just like every person has their own unique
fingerprint…everyone has a unique banding
pattern produced by their restriction
fragments in gel electrophoresis.
• 97% of our DNA is “junk” or non-coding and
is extremely different from any other persons
“junk” DNA.
• Forensics!!
Who committed the crime?
Suspect #
1 2
3
4
5 6
7
Bloodstain evidence from crime scene of
guilty person!
Gene Therapy!
• Used to identify a “bad/faulty” gene ( that
makes someone “sick”) …..and REPLACE it with a
“good” gene.
• Occurs in “embryo” development!
• Uses viruses to carry the DNA into and out
of the body.
Cloning
Uses a single cell from an adult organism to
grow an identical new individual.
“Dolly” 1997
Stem Cells and Homeotic Genes
• Stem cells – cells (early
in development) that
remain undifferentiated
and have the potential to
be any type of cell.
• Homeotic Genes –
genes that control
development of specific
locations in organisms.
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1. The use of organisms to perform practical tasks
B
D
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2. A technology that combines genes from different
sources into a single DNA molecule
L 3. A small, circular DNA molecule found in bacteria;
_____
separate from bacterial chromosome
G
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4. Cuts DNA at specific nucleotide sequences
I
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5. Complete collection of cloned DNA fragments from
an organism
K
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7. Any organism that has acquired genetic material
artificially
J
_____
8. Any genetically modified organisms whose source of
new genetic material is from a different species.
H
_____
9. Technique that involves making many copies of a
specific DNA sequence
F
_____ 10. Technique for sorting molecules like DNA by length
_____
11. Specific portion of DNA that varies among people
E
C 12. An individuals banding pattern on an
_____
electrophoresis gel, determined by DNA restriction
fragments
_____
13. Cell Type with the potential to differentiate into any
A
type of cell
A.
B.
C.
D.
E.
F.
G.
H.
I.
J.
K.
L.
Stem Cell
Biotechnology
DNA fingerprint
Recombinant DNA
Technology
Genetic Marker
Gel Electrophoresis
Restriction Enzyme
Polymerase Chain Reaction
Genomic Library
Transgenic
Genetically Modified
Organism
Plasmid