题干

下列关于“碱基互补配对原则”和“DNA复制特点”具体应用的叙述,不正确的是(  )

A:某双链DNA分子中,G占碱基总数的38%,其中一条链中的T占该DNA分子全部碱基总数的5%,那么另一条链中T占该DNA分子全部碱基总数的比例为7%

B:﹣个有2000个碱基的DNA分子,碱基对可能的排列方式有41000

C:已知一段信使RNA有30个碱基,其中A+U有12个,那么转录成信使RNA的一段DNA分子中C+G就有30个

D:将精原细胞的l对同源染色体的2个DNA都用15N标记,只提供含14N的原料,该细胞进行1次有丝分裂后再减数分裂,产生的8个精子中(无交叉互换现象)含i5N,14N标记的DNA的精子所占比例依次是50%、100%

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C

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    Today's workplace is unique in history.Never before have we seen people working together who represent such different backgrounds and experiences.This difference of age,race,gender,and work style makes it very difficult to organize and run a company.

    As a result,companies are looking for individuals who can manage a wide range of employees effectively. Increasingly,managers are discovering that age differences among workers are a major cause of concern.

    This has been an important realization.The management difficulties and challenges have led some experts to study intergenerational differences for an understanding of problems in the workplace.What they have discovered is interesting and may provide ways of improving working conditions in companies that employ individuals from different generations.

    The first thing to realize,they say,is that differences of opinion about the importance of work and how to get work done are not a coincidence.That is,it is not an accident that young employees will be different from older employees.In fact,if employers do not pay attention to these differences,it is possible that anger will build up between people and lead to difficulties in the company.

    Resentment(仇恨)between members of different generations,if not attended to(处理),can lead to extreme anger and unhappiness and even lasting enmity if people are not careful.That individuals from different generations should come to view each other as if they were from different sides of warring countries should not be surprising.

    It is natural for individuals from the same generation to form alliances(联盟),to come together for protection. Different generations represent different experiences in life,and these lead naturally to different opinions about oneself and one's approaches to work.

    If you were raised in a time of plenty,when products were readily available and relatively inexpensive,you would believe that prosperity is natural and expectable.If,on the other hand,you were raised in a time of scarcity,you would always be careful not to waste things for fear you would not have enough.You would make angry people who seem to believe that problems will always solve themselves.Such optimism in the face of difficulties would be a source of unhappiness between you and them.It is difficult,in such circumstances,to achieve a happy,agreeable atmosphere in the workplace.