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【单选题】
Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1. For questions 1—4, mark Y(for YES) if the statement agrees with the information given in the passage N(for NO) if the statement contradicts the information given in the passage NG(for NOT GIVEN) if the information is not given in the passage. For questions 5—10, complete the sentences with the information given in the passage. GENETICALLY MODIFIED FOODS Are genetically modified crops an environmental dream come- true or a disaster in the making? Scientists are looking for answers. The world seems increasingly divided into those who favor genetically modified (GM) foods and those who fear them. Advocates assert that growing genetically altered crops can be kinder to the environment and that eating foods from those plants is perfectly safe. And, they say, genetic engineering which can induce plants to grow in poor soils or to produce more nutritious foods will soon become an essential tool for helping to feed the world's burgeoning population. Skeptics contend that GM crops could pose unique risks to the environment and to health risks too troubling to accept placidly. Taking that view, many European countries are restricting the planting and importation of GM agricultural products. Much of the debate hinges on perceptions of safety. But what exactly does recent scientific research say about the hazards? The answers, too often lost in reports on the controversy, are served up in the pages that follow. Two years ago in Edinburgh, Scotland eco - vandals stormed a field, crushing canola plants. Last year in Maine, midnight raiders hacked down more than 3,000 experimental poplar trees. And in San Diego, protesters smashed sorghum and sprayed paint over greenhouse walls. This far - flung outrage took aim at genetically modified crops. But the protests backfired: all the destroyed plants were conventionally bred. In each case, activists mistook ordinary plants for GM varieties. It's easy to understand why. In a way, GM crops—now on some 109 million acres of farmland worldwide—are invisible. You can't see, taste or touch a gene inserted into a plant or sense its effects on the environment. You can't tell, just by looking, whether pollen containing a foreign gene can poison butterflies or fertilize plants miles away. That invisibility is precisely what worries people. How, exactly, will GM crops affect the environment- and when will we notice? Advocates of GM, or transgenic, crops say the plants will benefit the environment by requiring fewer toxic pesticides than conventional crops. But critics fear the potential risks and wonder how big the benefits really are. 'We have so many questions about these plants,' remarks Guenther Stotzky, a soil microbiologist at New York University. 'There's a lot we don't know and need to find out.' As GM crops multiply in the landscape, unprecedented numbers of researchers have started fanning into the fields to get the missing information. Some of their recent findings arc reassuring others suggest a need for vigilance. Fewer Poisons in the Soil? Every year U. S. growers shower crops with an estimated 971 million pounds of pesticides, mostly to kill insects, weeds and fungi. But pesticide residues linger on crops and the surrounding soil, leaching into groundwater, running into streams and getting gobbled up by wildlife. The constant chemical trickle is an old worry for environmentalists. In the mid - 1990s agribusinesses began advertising GM seeds that promised to reduce a farmer's use of toxic pesticides. Today most GM crops—main
A.
Y
B.
N
C.
NG
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举一反三
【单选题】患者,女性,60岁,因胃癌行胃大部切除术后13天,痊愈出院。正确的出院指导是
A.
定期针灸理疗
B.
绝对卧床休息
C.
经常消毒伤口
D.
定期回院复查
E.
进流质饮食
【多选题】下列原料中属于食用藻类蔬菜的有()。
A.
紫菜
B.
银耳
C.
发菜
D.
葛仙米
E.
石耳
【单选题】两个与非门构成的基本RS触发器的功能有置0、1和保持。电路中不允许两个输入端同时为( ),否则将出现逻辑混乱。
A.
0
B.
1
【单选题】食用藻类蔬菜有( ) 。
A.
树花
B.
薇菜
C.
石耳
D.
海带
【简答题】两个与非门构成的基本RS触发器的功能有置0、()和保持。电路中不允许两个输入端同时为0,否则将出现逻辑混乱。
【单选题】提高房地产经纪业务风险识别能力的基本前提是( )。
A.
树立风险防范意识
B.
合理承担风险
C.
建立监察稽核体系
D.
建立风险识别系统
【简答题】两个与非门构成的基本RS触发器的功能有置0、置1和()。电路中不允许两个输入端同时为低电平,否则将出现逻辑混乱。
【简答题】基本 RS 触发器有 、 、 三种可使用的功能。 电路中不允许两个输入端同时为 ,否则将出现逻辑混乱。
【简答题】基本 RS 触发器有 、 、 三种可使用的功能。 电路中不允许两个输入端同时为 ,否则将出现逻辑混乱。
【简答题】两个与非门构成的基本RS触发器的功能有( )、( )和( )。电路中不允许两个输入端同时为( ),否则将出现逻辑混乱。
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