首页
登录
职称英语
A new biotechnology procedure that could become commercially available in as
A new biotechnology procedure that could become commercially available in as
游客
2025-04-17
9
管理
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. [br] The tone of this passage is ______.
选项
A、critical
B、factual
C、humorous
D、romantic
答案
B
解析
本文作者没有表示任何观点,只对转基因技术做简单介绍,因此“factual,实际的”是正确答案,其他三项“critical批判的;humorous幽默的;romantic浪漫的”都不正确。
转载请注明原文地址:https://tihaiku.com/zcyy/4041053.html
相关试题推荐
Thenumberofticketsavailablewillbe______bythesizeofthestadium.A、dete
Billisanexampleofaseverelydisabledpersonwhohasbecome______atmanys
Themorepeoplearejammedtogether,themore______andirrationaltheybecome.A、
The______choiceforaconsumer,therefore,isthechoiceamongtheavailableone
Watchingnewsprogramatnighthasbecomean______partofthelivesofmostpeop
Inhisbookonbiotechnology,Rifkin_____that"fornow,themostimportantissue
She’sgotso______tolightmusicthatithasbecomeaconstantcompanionofher
Althoughtelevisionondemandhasnotyetbecomeamainstreamactivityinth
Althoughtelevisionondemandhasnotyetbecomeamainstreamactivityinth
Youcan’tcountonhim;he’sliableto______outwhenthingsbecomedifficult.A、b
随机试题
Anumberofscientificstudieshavefoundthattheamountofsugarweconsum
[originaltext]Ken:Hello,Rob.Rob:Hello,Ken...HelloBarbara.Comei
两个收益完全负相关的证券组成的资产组合,最小方差资产组合的标准差是()A.0
吸人性损伤患者防治肺部感染的基本措施是A.减少医院交叉感染 B.应用抗生素
基金公司应对不相容的岗位、公司资产与客户资产执行严格的( )。研究、投资决策、
下列关于我国QFII机制的意义,说法错误的是( )。A.可以为境内金融资产提供
Thechangeinthatvillagewasmiraculou
牙防小分队进驻某小学后,与校领导和卫生老师一起研究了学校口腔保健计划,就准备开展
根据增值税法律制度的规定,增值税一般纳税人购进的下列服务,不得抵扣进项税额的有(
玻璃幕墙密封胶的施工厚度应大于3.5mm,一般应控制在4.5mm以内。密封胶的施
最新回复
(
0
)