题干

如图表示从血液中制备核糖体的大致过程,对该过程的叙述中,不合理的是(    )

A:步骤①加入14C氨基酸的目的是为了步骤⑤阶段检测核糖体

B:步骤②的目的是破坏细胞膜

C:步骤①加入14C氨基酸的时间越长效果越好

D:步骤③④的目的是分离细胞器或细胞结构

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C

同类题5

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    More and more corporations are taking an interest in corporate social responsibility (CSR). CSR is made up of three broad layers. The most basic is traditional corporate charity work. Companies typically spend about 1% of pre-tax profits on worthy projects. But many feel that simply writing cheques to charities is no longer enough. In some companies, shareholders want to know that their money is being put to good use, and employees want to be actively involved in good works.

    Money alone is not the answer when companies come under attack for their behavior. Hence the second layer of CSR, which is a branch of risk management. Starting in the 1980s, with environmental disasters such as the explosion at Bhopal and the Exxon Valdez oil spill, industry after industry has suffered blows to its reputation.

    So, companies often responded by trying to manage the risks. They talk to non-governmental organisations (NGOs) and to governments, create codes of conduct(行为准则) and devote themselves to more transparency(透明)in their operations. Increasingly, too. they, along with their competitors, set common rules to spread risks.

    All this is largely defensive, but there are also opportunities for those that get ahead of the game. The emphasis on opportunity is the third layer of CSR: the idea that it can help to create value. If approached in a strategic way, CSR could become part of a company's competitive advantage. That is just the sort of thing chief executives like to hear. The idea of "doing well by doing good" has become popular.

    Nevertheless, the business of trying to be good is bringing difficult questions to executives. Can you measure CSR performance? Should you be cooperating with NGOs and you’re your competitors? Is there any really competitive advantage to be had from a green strategy?

    Corporate social responsibility is now seen as a mainstream. Big companies want to tell the world about their good citizenship with their devotion to social responsibilities. Done badly, CSR is often just window-dressing and can be positively harmful. Done well, though, it is not some separate activity that companies do on the side, a corner of corporate life reserved for virtue(美德):it is just good business.

     (Note: Answer the questions or complete the statements in NO MORE THAN TEN WORDS)