2. 外语
  3. The researchers put all the plants in a greenhouse to grow under normal conditions for forty days. Then, for fifteen days after

The researchers put all the plants in a greenhouse to grow under normal conditions for forty days. Then, for fifteen days after

admin2010-07-24  32
问题     The researchers put all the plants in a greenhouse to grow under normal conditions for forty days. Then, for fifteen days after that, the plants did not receive any【S1】______. The normal plants lost their green color. Finally, they lost their leaves. But the researchers say the【S2】______plants kept their leaves and their【S3】______.
    After the fifteen dry days, all the plants were watered again for a week. The transgenic plants returned to【S4】______growth, and their seed production was close to normal But the other plants all died.
    Rosa Rivera says the transgenic plants kept a【S5】______high water level. They also【S6】______to produce energy during the dry period, although at a reduced level. The amount of seeds they produced was close to normal. In addition, the researchers found that the plants could【S7】______on only thirty percent of the normal amount of【S8】______water. Yield loss was minor, they said.
    The【S9】______appeared late last year in the Proceedings of the National Academy of Sciences. The University of California has applied for patent【S10】______for the technology. The researchers expect to move forward with field testing of the transgenic tobacco in late August. They hope for similar results with crops like tomatoes, rice, wheat and cotton.

    A)similar        I)color
    B)keep           J)production
    C)water          K)level
    D)relatively     L)findings
    E)normal         M)continued
    F)survive        N)protection
    G)gained         O)irrigation
    H)transgenic
【S5】
选项
答案D
解析 此处应填副词。前文中说转基因植物抗旱，能基本保持在一个相对高水分的水平。除此，没有副词可选。
转载请注明原文地址:https://jikaoti.com/ti/IBEFFFFM
0

大学英语四级

相关试题推荐
随机试题
最新回复(0)