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
A new biotechnology procedure that could become commercially available in as little as two to four years is "transgenosis", whic
A new biotechnology procedure that could become commercially available in as little as two to four years is "transgenosis", whic
admin
2017-03-25
41
问题
A new biotechnology procedure that could become commercially available in as little as two to four years is "transgenosis", which permits scientists to create an animal with specific traits by adding, removing, inactivating, or repairing genes in an embryo. The additional genes can come from any source. For example, if a gene of interest occurs in mosquitoes—say, one that codes for resistance to a certain disease—it can be removed and placed in the embryo of a farm animal, the several strains of commercially useful transgenic farm animals that will probably emerge in the next few years could include leaner pigs, poultry resisting to influenza or other deadly diseases, sheep with wool that is easier to wash, and goats that produce valuable pharmaceuticals in their milk.
The simplest way to make transgenic animals is to inject a gene into a one-cell embryo and then implant the embryo in another animal. Under the right conditions, the new gene joins one of the embryo’s strands of genes. Each cell created as the embryo divides gets a copy of the new gene. An alternative technique is to incorporate the gene into a type of virus known as a retrovirus that has been modified so it cannot reproduce itself after entering a cell. The virus, which cannot cause disease, delivers the gene to the cell’s nucleus. Often this method is better than gene injection because a retrovirus always delivers just one gene, and the gene is always undamaged and complete.
The transgenic farm animals mentioned in this passage are______.
选项
A、pigs, cows and mosquitoes that have gone through the transgenic procedure
B、pigs, cows, sheep and chickens that have accepted additional genes
C、leaner pigs, poultry that produce pharmaceuticals and healthier sheep
D、leaner pigs, chickens resisting diseases and goats that produce milk with medicine in it
答案
D
解析
本题的依据句是第二段最后句“Often this method is better than gene injection because a retrovirus always delivers just one gene,and the gene is always undamaged and complete.”因此D项正确。
转载请注明原文地址:https://jikaoti.com/ti/KzyYFFFM
0
考博英语
相关试题推荐
Howmanyreallysufferasaresultoflabormarketproblems?Thisisoneofthemostcriticalyetcontentioussocialpolicyques
Chooseoneappropriatewordfromthefollowingwordbanktofillintheblanksnumberedfrom1to15inthepassagebelow.Chang
Everyyearthousandsofpeoplearearrestedandtakentocourtforshop-lifting.InBritainalone,aboutHK$3,000,000worthof
Veryfewscientists______completelynewanswerstotheworld’sproblems.
Severalinternationaleventsintheearly1990sseemlikelyto______,oratleastweaken,thetrendsthatemergedinthe1980s.
Thewonderswhichmedicalworkershavealreadybroughtaboutinthediagnosisandtreatmentofdiseasesuggestthatatimemayc
Researchershavestudiedthepoorasindividuals,asfamiliesandhouseholds,asmembersofpoorcommunities,neighborhoodsand
Directions:Doyouagreeordisagreewiththefollowingstatement?Peopleneversatisfiedwithwhattheyhave.Theyalwayswant
InGermany,incontrastwithFrance,friendshipismuchmoreclearlyamatteroffeeling.Adolescents,boysandgirls,fromdeeply
Mosttrappersworkedaloneandemergedfromthewildernessonlyfortheannualrendezvous,wheretheyhaggledandargueduntilth
随机试题
A.矢状线B.冠状线C.正中线D.水平线E.垂直线与人体矢状面平行的水平线
心理生理性失眠的特征有
牙髓电活力测验可以判断牙髓的
6岁男孩,尿少,水肿2天,血压130/90mmHg。尿常规:蛋白(++),红细胞25个/HP,白细胞15个/HP。应采取的紧急措施是
中毒性肺水肿的机制与临床表现。
根据设计要求,县发电厂应当建设储灰场用于防治粉煤灰的污染在实际施工中,筹建单位却未予建设在未经环境保护局验收批准的情况下,县发电厂于2003年1月开始生产生产中产生的大量粉煤灰污染大气,导致周围居民患病因此,居民们要求关闭该发电厂,县环境保护局做出了“发电
下面谱例中领唱与合唱的关系是()。
记忆是个被动保持信息的系统。()
请根据以下资料回答以下问题:该商场在2012年销售额最多的一类商品是()。
【T1】我要跟你讲讲文学是什么!不——只是但愿能做到,可实际上我做不到。(wish)对于文学的奥秘,只能略加阐释,做点提示,仅此而已。【T2】我就试着给诸位做点提示吧。(thinking)为此,我要引导你回顾一下你的历史,或者做一番遐想。【T3】比如
最新回复
(
0
)