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Unit 3B: Genetic Engineering • What are “biotech foods”? They are also called, GM foods, or genetically modified /engineered/altered food products. • Have you heard of this kind of food on the market? If yes, can you give an example? Words & Expressions (p.44) • Scientists are busy altering the genes: to change, to modify • …to create new varieties that are resistant to insects and to herbicides: immune, unaffected, able to defend itself against…; a chemical that destroys plants esp. weeds Words & Expressions • …the manipulation of DNA: control or operation • A revolution in food production: a drastic or great change • A battle between those who believe in its promise…: a war or fight; future success • Nutritional values: nutrition ~ nutritionary • Such potential benefits notwithstanding…: despite, in spite of, regardless of Words & Expressions • Humans have been altering generic traits: characteristics or quality • …by keeping seeds from the best crops…: agricultural produce • …by breeding varieties to make them taste sweeter: to produce (offspring) • …we’ve transformed the wild tomato: to change greatly or to convert • Teosinte with an “ear” barely an inch long: the part of a cereal plant such as wheat, that contains seeds or grains穀穗 • …can transfer just a few genes at a time between species that are not related at all: a segment of DNA, passed from parents to their offspring • …moth genes have been inserted into apple trees: an insect • Conventional breeding: ordinary, traditional • …to insert a gene or genes from an organism…: an individual form of life, creature • …deal with age-old farming problems: weeds, insects, and disease: very old, ancient; an undesirable plant growing wild Listening: What is genetically modified food? 1. Examples of strange GM organisms: • • • 2. Pigs that __________in the dark (glow) Chickens that grow without __________ (feathers) Goats that produce spider silk __________ (proteins) Traditional process of altering genes: • • • • 3. By picking organisms with desirable ________ and mating them together over and over again. (traits) Scientists call this process ___________ selection. (artificial) A classic example: from teosinte to corn Other examples: wheat, rice, _________, banana (almond) The difference in modern genetically modified food is the _________ and precision which we can make changes. (speed) • • 4. If the new organism comes from the same specie, scientists call it cisgenic. Cis means ___________. If it comes from different species, scientists call the new organism transgenic. Trans means ___________. (the same) (cross) Example: The fluorescent pigs glow green because they contain a gene from a luminescent __________ fish. (jelly) Recent transgenic GM food: • • • 5. Corns that make bacteria toxin poisonous to pests ___________ that make antifreeze protein (tomatoes) Cows that produce ___________ milk (human) Conclusion: • • All of the GM foods currently on the market have been thoroughly ____________. (tested) Personally, I’m waiting for a ____________ that I cut it in the dark. (tomato) Words & Expressions • None of the current biotech products have been implicated in allergic reactions…: be involved in; be related to; be responsible for • High levels of fumonisins toxin: poison • …grow in the wounds of the damaged corn: an injury, or a cut • A protein that causes reactions in humans who are allergic to nuts: nutritional substance found in meat and eggs; having an allergy • …other harmful proteins created through GM may slip by undiscovered: pass by or slip away • …in the function of the host DNA: the organism into which the foreign DNA is inserted • On the other hand, advocates of GE crops…: (n.) supporter, or defender (v.) to support, or to speak in favor of • …by offering an environmentally friendly alternative to pesticide: an option or choice; chemicals used to kill harmful insects Words & Expressions • …people are malnourished: not being provided with adequate nourishment • …GE can help address the urgent problem of food shortage and hunger: deal with • …vitamin A deficiency: not having enough of something (adj.) deficient: lacking • Skeptics claim that golden rice is little more than a public relations exercise…: someone who doubts; a promotion or advertisement • …which they say has exaggerated its benefits: overstated, or enlarged • Golden rice alone won’t diminish vitamin A deficiency: reduce • Their potential is enormous: huge, or great • If science proceeds with caution, testing new products thoroughly and using sound judgment: to go forward, continue, or go on; carefully, completely, fully; (adj.) wise, proper, or well-grounded