练习册

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  • 试题
    通过幻灯片向同学展示几种不同的设计风格.为了充分挖掘学生的英语潜力.我们希望学生用简短的句子.短语甚至单词谈谈他们的感受.喜欢的原因.Eg: I like the second picture because it is very bright and tidy. 【查看更多】

     

    题目列表(包括答案和解析)

    （6分）据图回答下列问题：

    （1）据图1，若某植物幼苗已表现出向光性，且测得其向光面的生长素浓度为m，则背光面生长素浓度范围是             。
    （2）据图1可知，除草剂灭草的原理是使杂草的生长素浓度大于       （填图1中字母）。
    （3）在探究生长素促进插条生根的最适浓度时，一名技术人员用几种不同浓度生长素溶液处理插条基部，然后在沙床中培养，观察生根情况。图2为生长素促进枝条生根的情况。请结合图1判断，在下列各项浓度值中，最好选用（   ）
    A．3mg·mL-1B．6 mg·mL-1C．9 mg·mL-1D．4.5 mg·mL-1
    （4）生长素的主要作用是促进细胞纵向伸长，其作用机理如图3所示，请回答下列问题：

    ①生长素作用的第一步是与细胞膜上的受体结合，形成“激素—受体复合物”，这一过程体现了细胞膜的              功能。
    ②实验发现，细胞在持续生长过程中，细胞壁将发生一定变化，出现这种现象的原因是由于              （填细胞器）为细胞壁添加了新的成分。
    ③此外，Ca2+ 还能激活细胞中的转录因子，它进入细胞核后，能引起         酶催化mRNA的合成。

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    仿写：

    根据题目要求，完成(A)、(B)两项书写任务。

    (A)假如你是Judy，请你根据你的成绩单，给你妈妈写一封信，汇报你的成绩。

    　　Dear Mom,

    　　How's it going? Things are fine here. I got my report card today. Luckily, I did OK this time. My English teacher said I was 1 . My math teacher said I was 2 and my PE teacher said I was 3 in class. However, my history teacher said I 4 . Another disappointing result was in science. My science teacher said I was a 5 student.

    　　Well, that's all about the news I have for now. I will have to try harder at science.

    Love,

    Judy

    (B)仿照上文，请你从不同的几个方面，向同学们介绍一下Peter的学习情况。

    This is Peter's report card. He did OK in some subjects. His PE teacher said he was good at 6 . His math teacher said he was a 7 student and his English teacher said he could speak English 8 . However, his history teacher said he could get better 9 . Another disappointing result was in music. His music teacher said he 10 .

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    以“Animals, our friends!”为题写一篇短文。

    要求：1）70词左右，开头已给出，不计入总词数。

    2）展开自己的想象，可以通过“dogs, cows, hens 等几种动物来进行说明。

    3）适当运用get on well with….; get …from…; guide dogs; the blind; milk; hens; eggs; interesting; for example; save 等词汇。

    4）意思连贯，语句通顺，书写工整。

    Animals, our friends!

    It is important to ________________________________________________________________

    _____________________________________________________________________________________

    _____________________________________________________________________________________

    _____________________________________________________________________________________

     

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    以“Animals, our friends!”为题写一篇短文。
    要求：1）70词左右，开头已给出，不计入总词数。
    2）展开自己的想象，可以通过“dogs, cows, hens 等几种动物来进行说明。
    3）适当运用get on well with….; get …from…; guide dogs; the blind; milk; hens; eggs; interesting; for example; save 等词汇。
    4）意思连贯，语句通顺，书写工整。
    Animals, our friends!
    It is important to ________________________________________________________________
    _____________________________________________________________________________________
    _____________________________________________________________________________________
    _____________________________________________________________________________________

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    写作

    上课铃响过5分钟了，Tom还没来上学。同学们议论纷纷并做出了种种不同的推测。请用must, might, could, can’t写出四种不同的推测。

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