Transcript File

Chapter 8
Biotechnology
What is Biotechnology?
• Biotechnology is the collection of technologies
applied to living organisms or substances
derived from living organisms in order to meet
a need or a want.
• In other words: Biotechnology is using living
things or stuff from living things to help us.
Traditional Biotechnology
Agriculture and Breeding
• Agriculture: developing better techniques for
farming.
• Making better tools
• Finding better planting methods (crop rotation)
• fertilizing methods
• Selective breeding: Choosing only the best crops
or animals to produce the next generation.
• With each generation, the resulting crops and animals are
closer to what we want. After many generations they may
be very different from their wild ancestors.
Most of the
technologies here
have been used for
thousands of years
Food Technology
• Using living organisms to transform one type
of food product into something different.
• Milk + enzymes  cheese
• Milk + bacteria  yogurt
• Cereal (barley) grain + yeast  beer
• Cereal (wheat) grain + yeast  bread
• Grape juice + yeast  wine
• Cabbage + bacteria  sauerkraut
Modern Biotechnology
Cell Cultures
• Cell culture is a laboratory technique used to
grow living cells outside of their natural
environment.
• This usually results in growing an increasing number of
cells in an artificial medium.
• A culture medium is what we grow the cell culture in,
usually a Petri dish that contains a gel with all the
necessary elements to promote cell growth.
a Petri dish
a Petri dish with growing cell culture
• Cell culture can also be done in test tubes
Bacteria grown in a test tube
Modern Biotechnology
Genetic Transformations
• A gene is a bit of DNA that controls one
feature of an organism; codes one protein.
• A genetic transformation is the modification of
one creature’s DNA by removing a gene,
changing a gene, or adding a gene from a
different species.
• After the creature’s DNA has been modified, it is called
a GMO (Genetically Modified Organism) or a transgenic
organism.
Examples of a G.M.O.
Spider DNA
Silk protein in goat milk
• Spider DNA has been inserted into goat cells, resulting in a goat that
produces spider-silk proteins in its milk. (biosteel, bullet proof skin)
• DNA from bacteria has been inserted into corn plants to make them
resistant to a disease caused by the European Corn Borer larva.
• DNA from
fireflies
or on
other
bioluminescent
has been inserted
See
pictures
page
246 and 247 oforganisms
your text book
into mice and other animals to make them glow in the dark.
firefly DNA
Glow-in-the-dark mouse
Steps in Producing a GMO
• Identify a need or desire (rice that contains
vitamin A)
• Identify the trait that meets the need (sweet
potatoes produce vitamin A)
• Identify and isolate the gene for the trait
• Replicate the gene
• Transfer the gene into the organism to be
organised
• Culture the genetically modified organism
Advantages of GMOs
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Can improve plant oil quality (soy, canola)
Can produce more nutritious foods (rice)
Can reduce need for pesticides. (corn, tomatos)
Can reduce allergic effects (peanuts, soy, rice)
Increased growth rate (G.M. Salmon*)
Less harmful manure (G.M. Pigs*)
Produce lactose-free milk (G.M. Cows*)
Produce milk more like humans (G.M. Cows*)
*These animal products are not currently legal for sale in Quebec
Concerns about GMOs
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Risk of creating a dangerous GMO
Risk of creating new allergies
Risk of reducing biodiversity
Risk that insect resistance could lead to
reduction of useful insects
• Risk that GMO herbicide resistance could
transfer to weeds.
• Legal questions regarding ownership of GMOs
spread by pollenation.
“Frankenfood”
A nickname given to food or crops that contain GMOs
• Genetic modification can
certainly improve crops,
or help them resist
disease,
• some people wonder if
they will have other
effects on us.
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Will they be as nutritious?
Will they have side effects?
What about diversity?
Who owns the rights to food?
What if we accidentally
develop a dangerous crop like
“Day of the Triffids”?
Cloning
• Cloning is the process of producing a
genetically identical copy of a living organism.
• Cloning is done by replacing the nucleus of an
unfertilized egg with a nucleus from a cell of the
organism to be cloned.
• Dolly the sheep, the first cloned mammal, was created
this way in 1997.
• Since humans are also mammals, it is theoretically
possible to clone human beings—however, nearly every
country has passed laws to stop human cloning!
Starbuck II
A bull cloned here in Quebec
R.I.P. Original Starbuck
Happy Birthday, er, Cloneday
Starbuck II
• The original Starbuck
was a championship
bull. When he died in
1998 breeders decided
to recreate him as a
clone.
• Although the cloning
was successful, they are
not allowed to sell any
products from him,
since it is illegal to sell
cloned products in
Canada.
Two Types of Human Cloning
• Reproductive cloning:
– Creates an individual who is genetically identical
to the person cloned. Note that being genetically
identical does not guarantee a similar personality
and does not give similar memories or knowledge.
• Therapeutic Cloning:
– Could grow tissue or organs for transplanting. An
embryo could be produced, and then “harvested”
for parts.
Experimental Moratorium
• In fact, there are many types of genetic
experimentation that are either illegal or
highly restricted in Canada and even more in
the United States.
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•
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•
•
Stem Cell Research (allowed, but with restrictions)
Human Genetic Modification (mostly illegal)
Human Cloning (illegal)
Animal Cloning (restricted, and sale of products illegal)
Animal Genetic Modification (restricted, and sale of
products illegal)
Modern Biotechnology
Applications in Agriculture and Food
Modern Biotechnology
Applications in Medicine and Health
• Immunity is the capacity to resist disease.
• If we have been exposed before, we are better
able to fight off the infectious agent that
causes the disease.
• The first time we are exposed, it takes our bodies over a
week to find out how to fight the disease
• The second time, it takes only 12 to 24 hours for our
body to start fighting the disease– and it does it better
the second time around.
Vaccination
• A vaccination deliberately infects you with an
attenuated (weakened) version of the disease.
• The weakened infectious agent is strong enough to
“teach” our immune system how to fight the disease.
• It is not strong enough to actually trigger the disease.
• A vaccine is a prepared substance that is able
to immunize a person against one or several
diseases.
• Live vaccines contain weakened, living infectious agents.
• Inactive vaccines contain chemicals (antigens are
proteins) from infectious agents.
Interesting Facts about Vaccination
• The first successful documented vaccinations
were performed by Dr. Edward Jenner in
1796
• He used a weak cowpox vaccine to immunize
people against more serious smallpox.
• Vaccination comes from the Latin word
“Vacca”, meaning “cow”. That’s because the
first vaccine came from a cow disease.
• Smallpox is now thought to be extinct. In just
200 years vaccinations got rid of a formerly
deadly disease.
Recommended Vaccinations
(most are recommended and covered by RAMQ)
Disease vaccine
Type
Age at 1st dose
Booster dose(s)
DTaP
Diptheria, Tetanus, Pertussis
inactive
2 months
4, 6, and 18 months
Then every 10 years
Polio- Hib (usually with DTaP)
Inactive
2 months
4, 6, and 18 months
Pneumococcus
Inactive
2 months
4, 12 months
and age 65
Influenza (flu)
Inactive
6 to 23 months
none
Annually if needed*
Chickenpox
Live
12 months
none
MMR
Measles, mumps, rubella
Live
12 months
18 months
Meningococcus
Inactive
12 months
None
Hepatitis B
Inactive
9 years
none
*each year a seasonal flu vaccine is developed in the autumn, and is recommended
only for people who are at high risk for catching the flu, and may not be covered by
the RAMQ.
Modern Biotechnology
Applications in Medicine and Health
• Infertility treatments:
• Used to allow a childless couple to conceive children
– 1. Ovarian Stimulation
• Medication is used to stimulate the ovaries into
developing more follicles and eggs than normal. Used if
a woman is not ovulating normally.
– 2. Artificial Insemination
• Sperm are injected directly into the uterus on the day
of ovulation. Used if sperm are having difficulty getting
through the cervix.
– 3. In vitro fertilization
• (see next slide)
In vitro fertilization
• Procedure:
(Test tube babies)
– Use ovarian stimulation so the woman will
produce more eggs.
– Retrieve eggs and sperm.
– The egg and sperm are mixed in a glass dish
(in vitro is Latin for “in glass”) where
fertilization occurs.
– The embryo created is transferred to the
uterus, where a (hopefully) normal
pregnancy occurs.
Louise Brown, the world’s first test tube
baby was born in 1978 
Modern Biotechnology
Applications in Medicine and Health
• Tissue and Organ Engineering
– Some of our body tissues, like our bones and skin,
are very good at repairing themselves.
– Others, like our nerves, do not repair themselves.
• Wouldn’t it be neat if all of our tissues could
repair themselves?
– Some animals, like salamanders, can re-grow
complete limbs. Cut off a salamander’s foot, and
it will grow back!
– Why can’t we do that?
Specialized Cells
• Most human cells are highly specialized.
• Specialized cells play a specific role in the human
body. When a specialized cell divides, it produces
cells that have the same function as it does.
– Muscle cells produce only muscle cells
– Liver cells produce only liver cells
– All differentiated cells, etc.
• Our cells cannot go back to the simpler forms they
had when we were embryos. This means that we
cannot rebuild lost organs.
Stem Cells
• There is another type of human cell, the Stem
Cell
• Stem Cells do not play any particular role in
the human organism, but they can divide
many times, and can transform into a variety
of specialized cells
– Stem cells are rare in adults (mainly in bone marrow)
– Stem cells are common in embryos (that’s how
embryos grow, change and repair themselves)
Stem Cell Research
• Scientists are researching the uses of stem
cells in repairing tissues and curing diseases.
• Some conditions stem cell research might
help:
• Nerve damage from diseases like Alzheimer's,
Parkinson’s or multiple sclerosis.
• Paralysis from spinal injury or strokes.
• Certain types of blood and lymph node cancer.
• Improved skin grafts for burn victims.
• Organ repair or replacement.
• Reversing the aging process.
Ethical Standards and Stem Cells
• Stem cell research is promising, but it is controversial
as well. Since most stem cells come from embryos,
rules have to be used to prevent people from
destroying embryos just for the sake of getting stem
cells.
• Embryos should not be sold nor stem cells obtained
through commercial transactions.
• Donations of embryonic tissue must be done of a
woman’s own free will.
• Donors must be informed, and consent given.
• Umbilical and placental stem cells can be used only
with both parent’s consent.
Modern Biotechnology Assignments
• Textbook Reading: pages 239 to 263
• Workbook pages 143 to 154