0  321242  321250  321256  321260  321266  321268  321272  321278  321280  321286  321292  321296  321298  321302  321308  321310  321316  321320  321322  321326  321328  321332  321334  321336  321337  321338  321340  321341  321342  321344  321346  321350  321352  321356  321358  321362  321368  321370  321376  321380  321382  321386  321392  321398  321400  321406  321410  321412  321418  321422  321428  321436  447090 

27.The students in the university are all taking courses     to a degree.

    A.lead           B.leading         C.led            D.to be leading

试题详情

26.There is no     in trying to talk George into joining us. He enjoys being alone.

    A.doubt          B.wonder        C.hope          D.point

试题详情

25.An advertisement is useful in    it can persuade customers to but the kinds of goods in the shop.

    A.that           B.which         C.what          D.whether

试题详情

24.I don’t mind her criticizing me, but     is how she does it that I object to.

    A.it             B.that           C.this           D.which

试题详情

23.      all her spare time to her study during the three years, Tedy finally took the first place in her school in the College Entrance Examination and received the admission notice from her dream university.

    A.Devoted        B.Having devoted   C.To be devoted    D.She had devoted

试题详情

22.After a hard ---fought campaign, Barack Obama won the US presidential election, and became

          President of the United States---the first African –American in       

country’s history to do so.

    A.the; the        B./; /            C./; the          D.the; /

试题详情

从A、B、C、D四个选项中,选出可以填入空白处的最佳选项,并在机读卡上将该选项标号涂黑。

21.----What does your Mum do?

   ----       

    A.She usually stays up late.            B.She is cooking.

    C.My mother is a teacher.             D.That’s great!

试题详情

54.(9分)右图是甲病(基因用A、a表示)和乙病(基因用B、b表示)两种遗传病的系谱图。

    请据图回答:

   (1)Ⅱ3和Ⅱ8均无乙病致病基因,则甲病的遗传方式为       。  乙病的遗传方式为         

  (2)Ⅲ11和Ⅲ12分别与正常男性结婚,她们怀孕后进行遗传咨询,了解到若在妊娠早期对胎儿进行检查,可判断后代是否会患这两遗传病。可供她们选择的胎儿检查措施如下:                        (   )

       A.染色体数目检测              B.性别检测

       C.基因检测                  D.无需进行上述检测

    请根据系谱图分析:

    ①Ⅲ11采取什么措施?   (填序号),原因是                

    ②Ⅲ12采取什么措施?   (填序号),原因是                

  (3)人类的F基因前段存在CGG重复序列。科学家对CGG重复次数、F基因表达和遗传病症状表现三者之间的关系进行调查研究,统计结果如下:

CGG重复次数(n)
n<50
n≈150
n≈260
n≈500
F基因的mRNA(分子数/细胞)
50
50
50
50
F基因编码的蛋白质(分子数/细胞)
1000
400
120
0
症状表现
无症状
轻度
中度
重度

    此项研究的结论:                             

    推测:CGG重复次数可能影响mRNA与          的结合。

试题详情


同步练习册答案