题目内容
10.Anyone who keeps a garden knows that most plants bend towards the sun to catch as much sunlight as they can.This is called"solar tracking".(36)AIf you observe a sunflower in the early morning,you will find it turning its face eastward; at sunset,on the other hand,its face will turn towards the west.
(37)FIn other words,what happens if you take a sunflower out of the garden bed and keep it in a completely dark room?
Surprisingly,the sunflower will continue its solar tracking without sunlight.It will bend,just as it did outside,eastward at sunrise and westward at sunset,even if there is not a single ray of light inside the dark room.This is a classic example of what scientists call a circadian rhythm (昼夜节律).What does it mean?(38)DIt's not directed by the environment.
Sunflowers do follow the sun,but they don't just"seek"sunlight.(39)GAlthough sunflowers don't bend with any purpose in mind,some scientists think they have evolved their solar tracking system over millions of years.According to this theory,the evolution helps sunflowers catch light more effectively,and the ones that catch light best are most likely to survive.As a result of this natural selection,we now have sunflowers that bend automatically.(40)EAfter a certain stage sunflowers stop following the sun and only face east.
A.Sunflowers are a well-known example of this.
B.Sunflowers are also an important source of food.
C.Wild sunflowers seen on roadsides don t follow the sun.
D.It is a daily cycle of behavior that is inside of living things.
E.However,that only happens when sunflowers are young plants.
F.But what if there's no sun for the sunflower to guide its solar tracking?
G.This is clear from the fact that sunflowers in darkness bend just as well.
分析 本文属于说明文阅读,作者通过这篇文章主要向我们描述了大多数植物都会朝着太阳弯曲,以尽可能多地捕捉阳光,这就是所谓的"太阳跟踪"
解答 36.A.推理判断题.根据后文If you observe a sunflower in the early morning,you will find it turning its face eastward可知向日葵就是一个很好的例子;故选A.
37.F.推理判断题.根据后文In other words,what happens if you take a sunflower out of the garden bed and keep it in a completely dark room可知询问如果向日葵没有太阳来指导太阳追踪呢;故选F.
38.D.推理判断题.根据前文This is a classic example of what scientists call a circadian rhythm (昼夜节律).What does it mean可知它是日常活动的循环,是生活的内部;故选D.
39.G.推理判断题.根据后文Although sunflowers don't bend with any purpose in mind,some scientists think they have evolved their solar tracking system over millions of years可知从在黑暗中的向日葵弯曲的事实可以明白;故选G.
40.E.推理判断题.根据后文After a certain stage sunflowers stop following the sun and only face east可知这是只有当向日葵是年轻的植物发生的;故选E.
点评 七选五阅读是完成性阅读,和完形填空很类似,不同的是一个选词,一个选句子.解题时,要注意上下文语境,充分考虑信息词(选项中和空格前后句子中相同或相近的词),选出最符合语境的句子.