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
21
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.
Which of the following is NOT true?
选项
A、After injection, the embryo gets a copy of the new gene as it divides.
B、The injection method is less good because the new gene sometimes fails to join the embryo’s genes.
C、The retrovirus multiplies after it enters the cell.
D、the incorporating method is less simple but better.
答案
C
解析
转载请注明原文地址:https://kaotiyun.com/show/SR1O777K
0
考博英语
相关试题推荐
Writeacompositionofatleast250wordsonthegiventopic"Myideaofthefutureworld"withthefollowingoutline.Presenty
A.Studythefollowinggraphcarefullyandwriteanessayin200words.B.Youressayshouldmeettherequirementsbelow.Outlin
I’vetoldyou________thatyoucannotgooutandplayuntilyou’vefinishedyourhomework.
Insteadofbeingsituatedatafixedcampus,theCityUniversityconductsclassesatvarioussitesdeemedconvenienttostudents.
By1916Canadahadplayedarespectableroleontheworldstage,arolethatwouldsoonhelpundoitscolonialstatus.
Thegovernment’spoliciesinthepastfiveyearshaveshowna(n)______inemphasizingthenecessityofimprovingthepeasants’
Itiswell-knownthattheretiredworkersinourcountryare______freemedicalcare.
EversinceGeoffreysentasizeablechequetoawell-knowncharityhe’sbeen______withrequestsformoneyfromallsides.
WhenIwassenttoprison,IreallyfeltIhad______myparents______.
Bysigninganapplication,Iaskedthatanaccount______formeandacreditcardissuedasIrequested.
随机试题
在场站施工图中,输送介质可标注名称或介质代号。()
气雾剂按医疗用途分类不包括
《招标投标法》规定,投标人相互串通投标或者与招标人串通投标的,投标人以向招标人或者与招标人串通投标的,投标人以向招标人或者评标委员会成员行贿的手段谋取中标的,中标无效,有违法所得的,将处以()。
LogisticsSystem1.Alogisticssystemconsistsofdifferentfunctionsandactivities,suchasthefollowing:Customerservice
近日,火星车在加勒陨坑拍摄的图像发现,火星陨坑内的远古土壤存在着类似地球土壤裂纹剖面的土壤样本,通常这样的土壤存在于南极干燥谷和智利阿塔卡马沙漠,这暗示着远古时期火星可能存在生命。以下哪项如果为真,最能支持上述结论?
试述交换机的存储转发方式和直通转发方式的优缺点。
A、 B、 C、 D、 C
以下命令中能够正确地画出矩形的是()。
Nowadays,thereisanewtrendamongcollegestudents.Manyofthemhavemovedouttoliveoutsidethecampus,someforlove,an
A、TohonorSwissheroeswhodiedinthewar.B、ToshowSwitzerlandwasneutral.C、TopaytributetoSwitzerland.D、Toshowgrati
最新回复
(
0
)