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2022年考博英语-桂林理工大学考试题库及全真模拟冲刺卷(附答案带详解)1. 单选题One of industrial agricultures biggest GMO crops may have just backfired (产生事与愿违的后果). Scientists have confirmed that corn-destroying rootworms have evolved to be resistant to the Bt corn engineered to kill them.Bt stands for Bacillus thuringiensis (苏云金芽孢杆菌), the name of the genetically modified corns “donor” organism. Bacillus thuringiensis is a naturally occurring soil bacterium that produces protein crystals that bind to certain receptors in the rootworms intestine (肠), killing it. For years, farmers have planted Bt corn as an alternative to spraying insecticides. Bt corn accounted for three-quarters of all corn planting in 2013. That may have to change.After finding a cornfield in Iowa in 2011 that was decimated (大幅度下降)by rootworm despite being planted with the Bt corn, Iowa State University entomologist Aaron Gassmann and his team began to study the pests interactions with the genetically modified organism (or GMO) corn in a lab. Their study, published Monday in the Proceedings of the National Academy of Sciences, describes the western corn rootworms rapid evolution after feeding on the engineered crop.But Bt corn is still capable of warding off other pests, so farmers will likely keep planting it. Except now theyll need to use pesticides to protect their crop from rootworms. As entomologists warned the Environmental Protection Agency in 2012, rootworm resistance means that the environmental advantage of Bt corn that it could be raised pesticide-free may disappear.“Unless management practices change, its only going to get worse,” Gassmann told Wired. “There needs to be a fundamental change in how the technology is used.”Scientists have predicted for years that this could happen, but warnings were repeatedly ignored by regulators and farmers. It takes millions of dollars to develop seeds like Bt, so engineering an alternative is not an attractive option. Instead, the authors of another study on rootworm Bt resistance, which focuses on Nebraska, take a biodiversity approach.“Crop rotation is the best tool,” University of Nebraska-Lincoln entomologist Lance Meinke told Farm & Ranch Guide. “Generally, one year of soybeans in a field with resistant western corn rootworms wipes out that population. The beetles will lay eggs that hatch, but when larvae (幼虫)try to feed on soybean plants, they dont find the nutrients they need and they die.”Crop rotation can suppress rootworm populations over time, reducing the threat posed by their new Bt resistance.But as entomologist Elson Shields of Cornell University told Wired, rootworm is just one symptom of an engineered seed trait “will fall under the same pressure,” said Shields, “and the insect will win.”1. What can we know about Bacillus thuringiensis?2. What inspired Aaron Gassmann to start his study?3. Which of the following is true, according to the passage?4. Lance Meinke thinks the best approach to the problem of rootworm Bt resistance is_.5. What is the problem with the GMO seed industry, according to Elson Shields?问题1选项A.It is a genetically modified organism.B.It is an alternative to spraying insecticides.C.It is a natural bacterium that kills rootworm.D.It protects rootworm from being killed by bacterium.问题2选项A.The great reduction of output of a cornfield in Iowa.B.The aim of boosting corn yield by 75% by 2011.C.The significance of corn rootworms rapid evolution.D.Aaron Gassmanns finding of a large number of rootworm.问题3选项A.People have not expected rootworm Bt resistance before.B.Bt resistance has a fundamental change in modern technology.C.It is economically impractical to entirely abandon Bt corn.D.Farmers prefer to use pesticides rather than plant Bt corn.问题4选项A.planting soybeansB.raising beetlesC.adding fertilizerD.rotating crop问题5选项A.Most of the entomologists failed to predict its future destiny.B.The GMO seed industry lacks long-term considerations.C.People mistakenly consider rootworm as the biggest trouble.D.It is very difficult for the GMO seed industry to win insects.【答案】第1题:B第2题:A第3题:C第4题:D第5题:C【解析】1.事实细节题。第一步,精准定位,定位到第二段第三句For years, farmers have planted Bt corn as an alternative to spraying insecticides(多年来,农民们一直种植Bt玉米作为喷洒杀虫剂的替代品),第二步,综合理解,这里是B选项的同意替换,B选项“是一种替代喷洒杀虫剂的方法”正确。A选项“是一种转基因生物”,定位到第二段第二句Bacillus thuringiensis is a naturally occurring soil bacterium that produces protein crystals that bind to certain receptors in the rootworms intestine, killing it(苏云金杆菌是一种天然存在的土壤细菌,它能产生蛋白质晶体,与根虫肠道中的某些受体结合,杀死根虫),由此可知苏云金杆菌不是转基因物体而是一种能够和害虫肠道里面的受体结合产生蛋白质结晶从而达到杀死害虫的天然细菌,是细菌的一种,这里属于反向干扰;C选项“是一种杀死根虫的天然细菌”,见A选项解析,是苏云金杆菌与害虫肠道的受体产生的蛋白质使虫子死亡,不是苏云金杆菌直接杀死虫子,这里属于曲意理解;D选项“它保护根虫不被细菌杀死”,见A选项,是侵害不是保护,这里属于反向干扰。2.事实细节题。第一步,精准定位,定位到第三段第一句After finding a cornfield in Iowa in 2011 that was decimated by rootworm despite being planted with the Bt
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