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 "transgenesis", whic
A new biotechnology procedure that could become commercially available in as little as two to four years is "transgenesis", whic
admin
2013-01-28
44
问题
A new biotechnology procedure that could become commercially available in as little as two to four years is "transgenesis", 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 places 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 bean 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.
In the first sentence, "to become commercially available" means ______.
选项
A、this procedure is available only on the market
B、this procedure can be used in producing better farm animals
C、This procedure can be used to promote business
D、People such as farmers can use this procedure in their production
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/qR1O777K
0
考博英语
相关试题推荐
Directadvertingincludesallformsofsalesappeals,mailed,delivered,orexhibiteddirectlytotheprospectivebuyerofanad
AUNofficialsaidthataidprogramswouldbe____untiltherewasadequateprotectionforreliefconvoy.
Thereisastoryofaverywickedmanwhodies.Beforehedied,hewas【C1】______theworstbecausetherewere【C2】______sinsheha
Itisnotforbiddentodreamofbuildingabetterworld,whichisbyandlargewhatthesocialsciencestrytohelpustodo.Ho
Thisisonlya________agreement;nothingseriousconcludedyetbyfar.
Comparingthetimescalesbetweenmanyfluepidemics,scientistscan____whenanotheronemighthappen.
TheCollector’sEditioncoinis______,andrepresentsatruecollector’streasuretobeappreciatedforgenerationstocome.
Thereareseveralpossibleexplanationsforthegreaterjob______inJapanincontrasttothegreatjobmobilityintheUnitedSt
ThereisnoquestionbutthatNewtonwasahighlycompetentMinisteroftheMint.Itwasmainlythroughhisefforts【41】theEngli
Today’sworkerisnolongerwillingtoworkinanauthoritariananddehumanizingenvironment.Workerswantmeaningintheirwork
随机试题
最早提出近代主权学说的思想家是()
向Excel工作表单元格里输入公式,其运算符有优先顺序,下列说法错误的是()
医疗器械广告的审批部门是
某市中级人民法院在对一起建筑施工合同纠纷的二审判决中,认定涉案施工企业不具备相应的资质等级,在判决作出后,该院院长发现该事实的认定存在重大错误。那么他应当()。
根据材料回答以下问题小明有一笔钱,考虑到当前银行存款利率较低,于是他决定用这笔钱来做证券投资。在理财规划师的建议下,小明购买了股票、可转换债券、基金、国债等产品。对小明来说,其购买的可转换债券,可在一定时期内将其转换为()。
每座城市的历史文化、地域环境、经济社会发展水平等各方面均存在差异,这就决定了每座城市的城市精神各不相同,甚至是特有的、不可复制的。同质化的城市精神,在本质上已经背离了城市精神的内涵,消磨了城市间的文化差异,显示不了城市本来的历史文化底蕴和人民精神面貌。这段
酒精呼气测试
Itwasasummerevening.Iwassittingbytheopenwindow,readinga【C1】______.Suddenly,Iheardsomeonecrying,"Help!Help!"
•Readthefollowingletter.•Choosethebestwordtofilleachgap.•Foreachquestion(19-33),markoneletter(A,B,CorD)o
Weenjoyfinefoodfromthefirsttastetothelast.Similarly,goodwritingissomethingwe【C1】______withpleasure.Andgoodw
最新回复
(
0
)