Pollution-fighting plants

Current Events 3
June 20- June 26
Tsunami Debris
• Tsunami triggered by a 9.0 undersea
earthquake off the coast of Japan on 11 March
• The tsunami swept an estimated 5 million tons
of debris into the Pacific Ocean.
• Roughly 70 percent of that sank right away,
which leaves maybe 1.5 million tons still
floating around.
• No radiation contamination
Tsunami Debris
• A large floating dock (~66’ x 19’ x 7’) that was
ripped from its pilings in Misawa, Japan by the
tsunami arrived on the shores of Newport in
central Oregon late on June 4 or very early on
June 5.
Tsunami Debris
Trouble on the Horizon for GM Crops?
• Pests are adapting to genetically modified
crops in unexpected ways
• Resistance of cotton bollworm to insect-killing
cotton plants involves more diverse genetic
changes than expected
Trouble on the Horizon for GM Crops?
• Cotton and corn have been genetically
engineered to produce toxins derived from the
bacterium Bacillus thuringiensis, or Bt.
• Over time, initially rare genetic mutations that
confer resistance to Bt toxins are becoming
more common as a growing number of pest
populations adapt to Bt crops.
Trouble on the Horizon for GM Crops?
• Two unrelated, dominant mutations in the field
• Dominant resistance is more difficult to
manage and cannot be readily slowed with
refuges, which are especially useful when
resistance is recessive
• Refuges consist of plants that do not have a Bt
toxin gene and thus allow survival of insects
that are susceptible to the toxin
• 2050 population 9 billion – demand for meat will grow
• 2010, a billion people suffered from chronic hunger
according to UN
• From an ecological perspective, insects have much
smaller footprint than livestock
• Insects are cold-blooded, making them 4-times more
efficient at turning food into meat than cattle
• Fried grasshoppers have 3-times the protein of cattle
• Because insects are so genetically distant from humans,
there is little likelihood of disease spreading – swine flu
• Many parts of the world eat bugs
– Mali children eat grasshoppers
– Australian Aborigines eat grubs
– Tarantuals in Venezuala
– Beetles in China
– Ancient Romans ate beetle grubs
– Anceint Greeks ate grasshoppers
• FDA allows certain levels of bugs in food
– In canned and fresh spinach, 50 aphis, thrips, or
mites per 100 grams
– Peanut Butter can have 30 insect fragments per
100 grams
– Chocolate can have 60 insect fragments per 10
Dengue Fever
• Like Malaria, Dengue is spread by a bite from an infected mosquito
• Dengue Fever is an extremely serious disease
Symptoms: mild and flu-like to high fever, rash, severe headache, pain behind the eyes,
muscle and joint pain
The joint pain can be so severe that Dengue has been given the name ‘breakbone fever’.
Nausea, vomiting, and loss of appetite are also common
• In the more severe form, known as Dengue Hemorrhagic Fever (DHF),
blood vessels start to leak and the blood fails to clot, causing bleeding from
the nose, mouth, and gums
• Without prompt treatment, the blood vessels can collapse, causing a critical
condition called Dengue Shock Syndrome
• About 25,000 people die from Dengue Fever every year
Dengue Fever
• Since the 1970s, the number of countries experiencing Dengue
outbreaks has grown from 9 to more than 100
• Today, up to 40% of the world’s population, or 2.5 billion
people, is thought to be at risk
Dengue Fever
• Aedes aegypti
• Eggs can survive for months without water,
allowing them to be transported all over the
• The life-cycle of a mosquito is about 3 weeks
– from hatching, to adult, to reproduction
Genetically Modified Mosquitoes
• Very small amounts of DNA injected into the
end of a mosquito egg
• In a very few eggs, the new DNA will be taken
up by the mosquito’s cells and will be cut and
pasted into the mosquito’s own genome
• If this happens in the sperm cells of a male
mosquito, or the egg-producing cells of a
female, the new DNA can be passed on to their
Genetically Modified Mosquitoes
• The GM males are then released into the
environment, where they mate with wild females
• As a result, the population as a whole is reduced
• Uses the natural instincts of the released male
mosquitoes to seek out females, so it is much
more effective than traditional means
• It is also species-specific: it affects only the target
pest, and doesn’t harm other insects
Genetically Modified Mosquitoes
• If the gene in the modified mosquitoes kills them, how does
that make them sterile?
• When the GM mosquitoes are reared in the presence of
tetracycline, it stops the GM protein from working: in
effect, it acts like an antidote
• So when we feed the modified mosquitoes with this
supplement in the lab, they stay perfectly healthy
• But when the male mosquitoes mate with females in the
wild, their children inherit the lethal gene
• Tetracycline is not present in the environment in sufficient
quantities to allow survival, so without the ‘antidote’ in their
diet, the children of the modified mosquitoes die
Example of Bizarre Genetic Engineering
• Glow-in-the-Dark cats
Example of Bizarre Genetic Engineering
• Pollution-fighting plants
Example of Bizarre Genetic Engineering
• Venomous cabbage
Example of Bizarre Genetic Engineering
• Goat Silk
Example of Bizarre Genetic Engineering
• Super Salmon
Example of Bizarre Genetic
• Vaccinating Bananas
Example of Bizarre Genetic Engineering
• Human hens

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