题干

长翅红眼雄蝇与长翅白眼雌蝇交配,产下一只染色体组成为XXY的残翅白眼雄蝇。已知翅长、眼色基因分别位于常染色体(A一长翅,a一残翅)和X染色体(B一红眼,b一白眼)上。在没有基因突变的情况下,下列分析正确的是

A:该染色体组成为XXY的白眼雄蝇体细胞中含有3个染色体组

B:产生该白眼雄蝇可能是父本雄蝇减数第一次分裂出错,XY同源染色体没有分离,产生异常的精子XY与正常卵细胞结合

C:产生该白眼雄蝇可能是母本雌蝇仅减数第一次分裂出错,此时与亲代雌蝇参与受精的卵细胞一起产生的三个极体基因型可能为AXb,AXb,a

D:产生该白眼雄蝇可能是母本雌蝇仅减数第二次分裂出错,此时与亲代雌蝇参与受精的卵细胞一起产生的三个极体基因型可能为AXb,AXb,a

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D

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    How to Become an Activist (活动家)

    Activists are people who see the need for change and devote their time to doing something about it.____If you are interested in it you can do so.

    ____This could be anything from a student club to a national organization (like the American Civil Liberties Union or the National Organizers Alliance). Most activist organizations offer different levels of involvement, so you can do whatever you feel most comfortable with, whether that means attending meetings and demonstrations or just donating a little money when you can.

    Volunteer your time. One of the best ways to make a difference is to volunteer your time. Reach out to organizations in your community that do work for your cause, and ask how you can help.

    Donate money or supplies.____If you can't afford to donate money to an organization that supports your cause, you may be able to donate other things they need, like clothing or canned food.

    Reach out to family and friends. Tell your family and friends about your cause, and invite them to get involved. If they are interested, share literature about your cause or just talk to them about what you have learned.____

    Promote your cause on social media. You can use social media to help keep your friends and followers informed about the causes you support.____Also, you can invite your friends to attend events or donate to fundraisers for your cause.

A. Take classes on issues related to your cause.

B. Join an organization that supports your cause.

C. They are driven by passion and a vision for a better future.

D. If you do volunteer work, invite them to volunteer with you.

E. Most activists or charitable organizations need resources to do their work.

F. Post useful articles and write about what you are doing to stay involved.

G. If you can't reach out to them in person, then try connecting to people online.