首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
In recent years a new farming revolution has begun, one that involves the 【21】______ of life at a fundamental level — the gen
In recent years a new farming revolution has begun, one that involves the 【21】______ of life at a fundamental level — the gen
admin
2010-07-06
7
问题
In recent years a new farming revolution has begun, one that involves the 【21】______ of life at a fundamental level — the gene. The study of genetics has 【22】______ a new industry called biotechnology. As the name suggests, it 【23】______ biology and modem technology through such techniques as genetic engineering. Some of the new biotech companies specialize 【24】______ agriculture and are working feverishly to duplicate seeds that give a high yield, that 【25】______ diseases, drought and frost, and that reduce the need for 【26】______ chemicals. 【27】______ such goals could be achieved, it would be most beneficial. But some have raised concerns about genetically engineered crops.
In nature, genetic diversity is created within certain space. A rose 【28】______ be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, 【29】______ , usually involves taking genes from one species and inserting them into 【30】______ in an attempt to transfer a desired characteristic. This could mean, 【31】______ , selecting a gene which leads to the production of a chemical with anti-freeze quality from an arc- tic fish, and inserting 【32】______ into a potato or strawberry to make it frost-resistant. In essence, then, biotechnology allows humans to 【33】______ the genetic walls that separate species.
Like the green revolution, 【34】______ some call the gene revolution contributes to the problem of genetic uniformity — some say even more so that geneticists can employ techniques 【35】______ as cloning and 【36】______ culture, processes that produce perfectly 【37】______ copies. Concerns about the erosion of biodiversity, therefore, 【38】______ . Genetically altered plants, however, raise new issues, such as the effects that they may have 【39】______ us and the environment. "We are flying blindly into a new era of agricultural biotechnology with high hopes, few constraints, and 【40】______ idea of the potential outcomes," said science writer Jeremy Rifkin.
【28】
选项
A、may
B、need
C、can
D、must
答案
C
解析
may表示可能性,need表示“需要,有必要”,must表示“必须”,can表示“能够”。由常识可知,同一物种是能够进行杂交的,因此选can最恰当。
转载请注明原文地址:https://kaotiyun.com/show/J8Dd777K
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
Supermarketshoppershaveneverbeenmorespoiltforchoice.Butjustwhenwethoughttraditionalsystemsofselectivefarmingh
Supermarketshoppershaveneverbeenmorespoiltforchoice.Butjustwhenwethoughttraditionalsystemsofselectivefarmingh
Throughouthistorytherehavebeenmanyunusualtaxesleviedonsuchthingsashats,Beds,Baths,marriages,andfunerals.Aton
Childrenwhogriptheirpenstooclosetothewritingpointarelikelytobeatadisadvantageinexaminations,【C1】________toth
Thebestestimateofhumanity’secologicalfootprintsuggeststhatitnowexceedstheEarth’sregenerativecapacitybyaround20
WhydoesDr.Johnsonsuggestbuildingagreenhousenearapowerstation?Whichofthefollowingcanbeusedasfertilizer?
AccordingtoCasey,whatdodesignersoftenforgetindesigningasystemoraproduct?AccordingtoCasey,thelikelihoodofhu
Whichofthefollowingcanbethebesttitleforthepassage?WhichofthefollowingrespectsdidNOThelpNewYorkbecomethe
AccordingtoGertrudeMongella,theequalitybetweenwomenandman______.Accordingtothepassage,whichofthefollowingis
Howmanyfactorscouldshapepublicopinion,asmentionedinthetext?WhichofthefollowingisTRUEaccordingtothepassage?
随机试题
A.钳刮术B.RU486+米索前列醇引产C.天花粉羊膜腔内引产D.利凡诺羊膜腔内引产E.水囊引产
引起工型呼吸衰竭的常见病因是
代偿患者自护方面的不足属于奥伦护理系统结构的()。
某房地产开发公司通过招标出让方式取得了一宗毛地的使用权进行住宅和商业房地产开发。该房地产开发公司未销售的已竣工商品房在会计科目中归为()类。
(2007年)∫0+∞xe-2xdx等于()。
生产力的发展、私有制的产生,是警察产生的()。
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性。
软件的(51)是指软件从一种计算机系统转换到另一种计算机系统运行的难易程度。在规定的条件下和规定的时间间隔内,软件实现其规定功能的概率称为(52)。
窗体Caption属性的作用是()。
根据汉字国标GB2312-80的规定,存储一个汉字的内码需用的字节个数是()。
最新回复
(
0
)