题干

质粒是基因工程中最常用的运载体,它存在于许多细菌体内。质粒上有标记基因如右下图所示,通过标记基因可以推知目的基因是否转移成功。目的基因插入的位置不同,细菌在培养基上的生长情况也不同。根据表中的细菌的生长情况判断,目的基因插入的位置是

 
细菌在含氨苄青霉素培养基上生长情况
细菌在含四环素培养基上生长情况

能生长
能生长

能生长
不能生长

不能生长
能生长

A:①是c,②是b,③是a

B:①是a和b,②是a,③是

C:①是a和b,②是b,③是a

D:①是c,②是a,③是

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A

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    Let's look back all these years you've gone through, what have you done for your life? Are you spending your time wisely to make your life worthwhile? Neal Wu shared some ways we should do to make our short time of life meaningful, find out what you need to do next:

    a. Make friends as opposed to networking

    Your friends will go a lot further than the professional contacts you make, especially since only one of the two groups is invested in your personal happiness.

    b. Become an expert by learning as much as you can and deeply seeking out the things you are curious about

    Find the things you enjoy and practice the skills you want to develop. If you can achieve expertise then it will be easy to obtain an audience.

    c. Volunteer to help out those less fortunate

    In the process you will gain a ton of new perspective and will better understand other people's real problems. In a society that always looks upward, these people are being forgotten easily.

    d. Become as independent as possible

    Even though you work in a big company, you should constantly make small steps to reduce your dependence on your job. Write a book, build an app, or start a small business on the side. Release your inner entrepreneur.

    e. Don't spend too much time worrying about your personal brand

    Accomplish(完成) things, and the recognition will follow.

    f. Stop treating life as a competition and do things for their own sake

    Genuine(真正的) interest should be what drives you to improve yourself, rather than a desire to beat others. Find a community of people who are interested in the same things as you do, and drive each other to keep improving.