微生物对物质降解与转化的特点。

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问题:

微生物对物质降解与转化的特点。

考点:环境生物学环境生物学题库
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若|2x3|+|3y+2|=0,则xy=_____.

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Having checked the doors were closed, and ______ all the lights were off, the boy opened

the door to his bedroom.   [ ]

A. that            

B. why            

C. when              

D. where

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第四节:阅读理解(共20小题,每小题2分,满分40分)

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

A

Science Daily -------- Dutch ecologist Roxina Soler and her colleagues have discovered that subterranean(地下的)and above ground herbivorous(食草的)insects can communicate with each other by using plants as telephones. Subterranean insects issue chemical warning signals through the leaves of the plant. Thus, aboveground insects are warned that the plant is already “ occupied”.

In recent years it has been discovered that different types of aboveground insects develop slowly if they feed on plants that also have subterranean residents and vice versa(反之亦然). It seems that a system has developed through natural selection, which helps the subterranean and aboveground insects to communicate with each other. This avoids unnecessary competition.

Through the “green telephone lines”, subterranean insects can also communicate with a third party, namely caterpillars(毛虫). Parasitic wasps(寄生的黄蜂)lay their eggs inside aboveground insects. The wasps also benefit from the signals sent by the leaves, The communication between subterranean and aboveground It is still not clear how widespread this phenomenon is.

This research was carried out at the Netherlands Institute for Ecology by Roxina Soler, Jeffrey Harvey, Martijn Bezemer, Wim van der Putten and Louise Vet. was funded by the Free Competition of NOW Earth and Life Sciences.

41. After finding a plant occupied by root-eating insects, aboveground insects will usually ________.

A. send out warning signals

B. choose to leave the plant

C. fight with the root-eating insects

D. compete with them for the same plant

42. Aboveground insects will develop more quickly if their food plants _______.

A. have more green leaves

B. get more water and sunlight

C. are often visited by parasitic wasps

D. are not occupied by root-eating insects

43. The underlined part “a third party” in Paragraph 4 refers to ______.

A. caterpillars               B. root-eating insects    

C. parasitic wasps          D. aboveground insects

44. What is the best title for the passage ?

A. Insects use plants as “telephones”

B. How do animals avoid competition

C. The living habit of different insects

D. Communication between different insects

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假设一国因货币供应量过快扩张形成通货膨胀,该国央行应该设法( )。

A.扩大再贷款B.直接购买政府债券C.降低法定准备率D.降低存款利率以提高通货比率

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请根据以下信息回答问题:

若一个卵原细胞的一条染色体上的某基因在复制时一条脱氧核苷酸链中一个A替换成T,则由该卵原细胞产生的卵细胞携带该突变基因的概率是()

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