Questions 47 to 56 are based on the following passage.
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 (47) . The normal plants lost their green color.
Finally, they lost their leaves. But the researchers say the (48)
plants kept their leaves and their (49) .
After the fifteen dry days, all the plants were watered again for a week.
The transgenic plants returned to (50) growth, and their seed
production was close to normal But the other plants all died.
Rosa Rivera says the transgenic plants kept a (51) high
water level. They also (52) 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
(53) on only thirty percent of the normal amount of
(54) water. Yield loss was minor, they said.
The (55) appeared late last year in the Proceedings of
the National Academy of Sciences. The University of California has applied for
patent (56) 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