Question

【题目】 Scientists don’t know yet whether cell phones are bad for the brain.【1】

In the experiment, the 47 participants may have looked a little strange. Each of them had two Samsung cell phones tied to his or her head—one on each ear.【2】 The phone on the right ear played a message for 50 minutes, but the participants couldn’t hear it because the sound was off. After 50 minutes with two phone attached to their heads, the participants were given PET scans. The PET scan is a way to take a three-dimensional picture of how the inside of the bodyworks.

The PET scan showed that the left side of each participant’s brain hadn’t changed from the way it was before the experiment.【3】 These right-side brain cells were using almost as much glucose as the brain uses when a person is talking. This suggests that brain cells there were active even without the person hearing or talking anything. This activity, the scientists say, was probably touched off by radiation from the phone.

【4】 They release different amounts of radiation depending on whether a person is talking or listening, the type of phone, the number of people using phones nearby, and the distance to the nearest cell phone tower. All of these changes make it difficult to collect evidence about any health risks of cell phones, since exposure to radiation can vary.

So for those who don’t want to wait to find out for sure whether cell phones are bad for the brain, there are ways to talk more safely.【5】

A.The phone on the left ear was off.

B.So an experiment was done to attempt to find it out.

C.People should avoid having a long conversation by using cell phones.

D.Cell phones do not always give out the same amount of energy.

E.You can have short conversations, use a speakerphone to keep the phone away from your head.

F.The right side of the brain, however, had used more glucose, which provided fuel to brain cells.

G.From the PET scan the differences between the two sides of the brain were observed.

Answer 1

【答案】

【1】B

【2】A

【3】F

【4】D

【5】E

【解析】

本文是一篇说明文。短文介绍了下次打电话可要记住不要超过50分钟，因为实验表明使用耳机接听电话超过50分钟，耳机会发出一种辐射。而这种辐射会对大脑有一定的影响。

【1】空格上文Scientists don’t know yet whether cell phones are bad for the brain.讲述科学家不知道是否手机对大脑不好，下文第二段In the experiment可知，进行了一个实验，故选项B“所以做了一个实验来试图找出它。”符合，上文是原因，空格处是结果，so是关键词，下文的the experiment指代此处的an experiment。故选B。

【2】空格上文Each of them had two Samsung cell phones tied to his or her head—one on each ear.讲述参与者每个人都有两部三星手机，绑在他或她的头上——每只耳朵上有一部。空格下文The phone on the right ear played a message for 50 minutes说明右耳上的电话播放了50分钟的信息，A项“左耳的电话关机”，符合，分别介绍了两个耳朵上的手机。故选A。

【3】空格下文These right-side brain cells were using almost as much glucose as the brain uses when a person is talking.讲述这些右侧的脑细胞使用的葡萄糖几乎和一个人说话时大脑使用的葡萄糖一样多。可推断，空格处讲述了右侧的脑细胞，因此推断F项“然而，右脑消耗了更多的葡萄糖，为脑细胞提供了能量。”符合语境，故选F。

【4】空格下文“They release different amounts of radiation depending on whether a person is talking or listening...”讲述他们释放不同数量的辐射取决于一个人是否在说话还是在倾听等……，因此推断手机并不总是发出同样的能量。故选D。

【5】空格上文讲述因此，对于那些不想等待确定手机是否对大脑有害的人来说，有一些方法可以更安全地交谈。因此推断空格处说的是解决办法，E项“你可以进行简短的交谈，用免提电话让手机远离你的头。”符合语境，故选E。