题干

在雄果蝇的某细胞中,染色体分别向两极移动,下列有关叙述正确的是(    )

A:如细胞中有同源染色体,则其核DNA分子数是体细胞的两倍

B:如果细胞中有两条Y染色体,则染色体数一定体细胞的两倍

C:正在进行DNA分子复制,染色体DNA一定由母链组成

D:如细胞中染色体数与其体细胞的相等,则一定没有染色单体

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A

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    The percentage of women working in technology has decreased since the 1990s.Women make up only a quarter of all jobs in computer and math professions.I think all girls should learn how to code(编码).Here is why.

    If we want to be part of one of the fastest growing job markets out there,we need to jump on board!Over the last ten years the growth in STEM jobs has been three times faster than that in non-STEM fields.Women will never be able to keep up with men in the professional workplace if we don't join the fastest growing fields.

    Just like hundreds of years ago,people who could read and write controlled the future,and now those who are at home with technology will shape the world we live in.You can use coding in every aspect of your life,even if you don't enter a field that involves coding.You cant use coding to create your own website or to program games.You can animate your YouTube videos,or make graphic designs.Programming is now being used in every profession, including medicine and airplane design.

    You can have fun creating your own website,programming a robot to get the remote for you when you're lying on the couch,photoshop pictures to change the color scheme to something better than the Instagram filters,and so much more.Coding allows you to realize your wildest dream,and create anything you can imagine.Coding allows you to rule the world.

    It's not very hard to learn to code.You could learn to code on YouTube,in the Girls Who Code club;you could take a free course online on Code Academy;you could even just Google how to code.

You learned to read,you learned to drive-now learn to code.