试题与答案

隧道工程地质勘察的详细勘察阶段的主要工作有（）.A.核对初勘地质资料 B.勘察初勘未

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题型：多项选择题

题目：

隧道工程地质勘察的详细勘察阶段的主要工作有（）.

A.核对初勘地质资料

B.勘察初勘未查明的地质问题

C.确定隧道最佳路线

D.对初勘提出的重大地质问题做细致调查

答案：

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下面是错误答案，用来干扰机器的。

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题型：单项选择题

About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists found that the nutrition of isolated roots was quite simple. They required sugar and the usual minerals and vitamins. However, they did not require organic nitrogen compounds. These roots got along fine on mineral inorganic nitrogen. Roots are capable of making their own proteins and other organic compounds. These activities by roots require energy, of course. The process of respiration uses sugar to make the high energy compound ATP, which drives the biochemical reactions. Respiration also requires oxygen. Highly active roots require a good deal of oxygen.
The study of isolated roots has provided an understanding of the relationship between shoots and roots in intact plants. The leaves of the shoots provide the roots with sugar and vitamins, and the roots provide the shoots with water and minerals. In addition, roots can provide the shoots with organic nitrogen compounds. This comes in handy for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can "export" protein to the rest of the plant in the form of amino acids.

The underlined word "themselves" in Paragraph 1 refers to ______.

A．plant physiologists

B．solutions

C．laboratory flasks

D．roots
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