题干

某中学九年级1班全体同学的综合素质评价“运动与健康”方面的等级统计如图所示,

其中评价为“A”所在扇形的圆心角是(  )

A:120° 

B:108° 

C:90°

D:30°

上一题 下一题 0.0难度 选择题 更新时间:2018-11-13 06:25:16

答案(点此获取答案解析)

B

同类题1

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    A hobby is an inverstment of time. It also can be an investment of money and commitment. Many people choose to developing more than one type of hobby. ____ When it comes to choosing the hobby, consider the following factors.

    Hobbies are usually an activity of some sort that brings out a certain skill that you have. When you have a talent like painting or woodworking, it can be easy to determine which hobby suits your skill. ____ Skill can be developed and challenged as you go along. It is not a necessary requirement. A hobby is fitting because you love it, not because you're a professional at it.

    Some people particularly enjoy taking part in hobbies that they can do in a group with others. It can be a lot more fun to become a member of a hobby group than to sit alone in your basement. ____ It's important to share interests and network with other hobby enthusiasts that do what you do.

    Hobbies are generally an activity that you undertake because of the joy it brings you. Of course many people have discovered the joy that also comes with a hobby that earns you a living.  ____ Just make sure you make the choice that fits your lifestyle and personal preference.

    ____ But most of the skilled hobbies like art, building or writing have a series of lessons or tutorials that you can take to further your skills. In some cases it's a really good idea to take lessons, especially if you are clueless as to where or how to begin. Step by step books for most hobbies can often be found in bookstores as well.

A. However, hobbies don't have to be skill related.

B. Most hobbies can easily be done within your own home, at your leisure.

C. Look one up or start your own.

D. Read hobby books to learn more about your chosen hobby!

E. Make a list of things that you enjoy or don't know about.

F. It can be a necessary part of selecting the hobby that is right for you.

G. Whether it's full time, part time or not at all, you must decide whether your hobby applies to you

同类题5

AS综合征是一种由于患儿脑细胞中UBE3A蛋白含量缺乏导致的神经系统发育性疾病.UBE3A蛋白由位于15号染色体上的UBE3A基因控制合成,该基因在人脑细胞中的表达与其来源有关:来自母方的UBE3A基因可正常表达,来自父方的UBE3A基因由于邻近的SNRPN基因产生的反义RNA干扰而无法表达(如图1所示).请分析回答以下问题:

(1)UBE3A蛋白是泛素﹣蛋白酶体的核心组分之一,后者可特异性“标记”P53蛋白并使其降解.由此可知AS综合征患儿脑细胞中P53蛋白积累量较____ .检测P53蛋白的方法是____ .细胞内蛋白质降解的另一途径是通过____ (细胞器)来完成的.

(2)由于UBE3A基因和SNRPN基因____ ,所以它们的遗传关系不遵循自由组合定律.对绝大多数AS综合征患儿和正常人的UBE3A基因进行测序,相应部分碱基序列如图2所示.由此判断绝大多数AS综合征的致病机理是:来自____ 方的UBE3A基因发生____ ,从而导致基因突变发生.

(3)研究表明,人体非神经组织中的来自母方或父方的UBE3A基因都可以正常表达,只有在神经组织中才会发生UBE3A基因被抑制的现象,说明该基因的表达具有____ 性.

(4)动物体细胞中某对同源染色体多出一条的个体称为“三体”.现产前诊断出一个15号染色体为“三体”的受精卵是由正常卵细胞与异常精子受精形成的,其UBE3A基因全部正常.该受精卵可随机丢失一条15号染色体而完成胚胎发育,则发育成AS综合征患者的几率是____ (不考虑基因突变,请用分数表示).

(5)丙种球蛋白缺乏症(XLA)是一种伴X染色体隐性遗传病,某家族中的XLA男性患者在未接受有效治疗的前提下,一部分幼年夭折,一部分能活到四、五十岁.请分析出现这种情况可能的两点原因:____ .