棉籽中提取的棉酚是抗癌药品有效成分,市场价格相当于黄金价格的60倍.棉酚的结构可

题型:选择题

问题:

棉籽中提取的棉酚是抗癌药品有效成分,市场价格相当于黄金价格的60倍.棉酚的结构可表示如下,下列有关说法不正确的是(  )

A.棉酚可跟NaOH、FeCl3、Br2溶液反应

B.棉酚有较强的还原性,在空气中易被氧化

C.用1H核磁共振谱可证明棉酚分子中有9种氢原子

D.棉酚完全燃烧后只生成二氧化碳和水两种产物

考点:有机物的官能团有机物分子的空间构型有机物按官能团的分类
题型:选择题

阅读理解。

     There are many kinds of ants (蚂蚁) in America. One kind is very strong. People are afraid of it, and

 animals are afraid of it, too.

     These ants move in large groups. They eat all the animals on their way. They can kill and eat  elephants

  and they can eat wood (木头) houses . Sometimes the ants can kill people. When the ants come near,

 people leave their homes. But people are sometimes glad after the ants pass through , because they can

 see no insects (昆虫) or snakes (蛇).

1. Some ants in America can be very _____.

    A. heavy          

    B. strong        

    C. light      

    D. thin

2.  People  and animals fear (害怕) _____.

    A. one kind of ants      

    B. all kinds of ants

    C. small ants          

    D. big ants

3. People get away from the ants because _____.

    A. they can eat and kill elephants    

    B. they can also eat wood houses

    C. they travel in large groups        

    D. they can even kill people

4. Why do the insects and snakes disappear (消失) after the ants pass through?

    A. They hide themselves under the ground.

    B. They move to other places before the ants come.

    C. The ants have killed and eaten the insects and snakes.

    D. People have killed the insects and snakes.

5. Which is the best title (题目) for the story ?

    A. Ants      

    B. American    

    C.A Big Ant      

    D.A Strong Ant

题型:选择题

在海拔1000m的天山上某处,做托里拆利实验,水银柱的高度将______760mmHg(填“高于”“低于”),在此处与海平面相比较,水的沸点将______.(填“降低”“升高”)

题型:选择题

原核生物中某一基因的编码区起始端插入了一个碱基对。在插入位点的附近,再发生下列哪种情况有可能对其编码的蛋白质结构影响最小[ ]

A.缺失4个碱基对

B.增加4个碱基对

C.缺失3个碱基对

D.置换单个碱基对

题型:选择题

某市西城区建委根据市政府总体规划,对某大街实施改造,刘某房屋位于改造区。某日,西城区建委改造建设指挥部下达住房拆迁通知,刘某未搬迁。数日后,区建委工作人员带领20余人强行拆除了刘某房屋,刘某不服提起行政复议,则可以作复议机关的是()。

A.省政府

B.市政府

C.西城区政府

D.西城区建委

题型:选择题

秦皮中所含的草酸钙结晶是()

A.方晶

B.簇晶

C.棱晶

D.柱晶

E.砂晶

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