填空题 A lot of people think we could be headed for trouble by tampering with Mother Nature and producing genetically altered food. But those who 1 say it"s no more unnatural than traditional selective breeding, to say nothing about 2 and chemical pesticides.
Most Canadians regularly eat bio-engineered food. Anyone who consumes cheese, potatoes, tomatoes, 3 is taking in genetically modified (GM) food. In addition, 4 contain GM ingredients. In fact, around 65% of the food we get from the shops has some genetically modified component. GM food does not 5 in Canada, so most of us don"t know we are eating it. Some of the items that have 6 GM material might surprise you. They include chocolate bars, baby food, margarine, 7 , ice cream, 8 , cereals, and cookies.
9 have used GM foods for centuries; if they hadn"t, we"d probably still be 10 . They"ve refined the foods we eat through selective crossbreeding, combining different types of wheat, and 11 . Today, however, genetic engineering is no longer just a case of mixing different varieties of 12 . Now, genes from completely different life forms are being combined—fish genes into tomatoes to 13 , for example.
Such "tampering with Nature" makes a lot of people anxious. They wonder if the foods that come out of genetic modification are 14 . Scientists say they are completely safe; GM is just a way of 15 to make it possible for them to survive without the use of pesticides and to 16 . But the 17 that scientists said that nuclear power and the toxic insecticide DDT were also completely harmless.
Supporters of GM foods 18 . They say producing GM food is a move in the right direction, that it will 19 , the environment, and the economy. They are convinced it will solve the world"s hunger problems, lead to a drop in pesticide and herbicide use, and result in 20 .