题干

调节电子显微镜观察A,B,C的细胞内部结构,观察到细胞结构a﹣d具有下列特征:a、b、c均由双层膜构成,并且都含有DNA,其中a膜上具有小孔,而b、c没有小孔.d由两个互相垂直的结构构成,与细胞的有丝分裂有关.将关于试样A,B,C的细胞结构有无作如下整理(+:存在;﹣:不存在):

细胞结构

a

b

c

d

试样A

试样B

+

+

+

试样C

+

+

+

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阅读下面短文,在空白处填入1个适当单词或括号内单词的正确形式。

    Chinese architecture is a style that has taken shape in East Asia over many centuries. The structural principles of Chinese architecture have remained largely ____ (change), the main changes being only the decorative details. Since the Tang Dynasty, Chinese architecture  ____ (have) a major influence ____ the architectural styles of Korea, Vietnam, and Japan.

    The architecture of China is as old as Chinese civilization. From every source of information, there is strong ____(evident) that the Chinese have always enjoyed a native system of construction that has kept its principal characteristics from old times to the present day. Over the large area from Chinese Turkistan (突厥) to Japan, the same system of construction is popular and this is the area of Chinese cultural influence.

    Throughout ____ 20th century, western-trained Chinese architects have tried ____ (combine) traditional Chinese designs into modern architecture, with great success. Moreover, the pressure for urban development throughout contemporary China required higher speed of construction and higher floor area ratio (容积率),____ means that in the great cities the demand for traditional Chinese ____ (build) has declined in favor of modern architecture. ____ the traditional skills of Chinese architecture,____ (include) major and minor carpentry (木工), and masonry (石工), are still applied to the construction of vernacular architecture in the large rural area in China.