学位英语

第4部分：阅读理解(第31～45题，每题3分，共45分)下面有3篇短文，每篇短文后有5道题。请根据短文内容，为每题确定1个最佳选项。

Making Light of Sleep

All we have a clock located inside our brains. Similar to your bedside alarm clock, your internal clock runs on a 24-hour cycle. This cycle, called a circadian (昼夜节奏的，生理节奏的) rhythm, helps control when you wake, when you eat and when you sleep.

Somewhere around puberty (青春期), something happens in the timing of the biological clock. The clock pushes forward,, so adolescents (青少年的) and teenagers are unable to fall asleep as early as they used to. When your mother tells you it's time for bed, your body may be pushing you to stay up for several hours more. And the light coming from your computer screen or TV could be pushing you to stay up even later.

This shift is natural for teenagers. But staying up very late and sleeping late can get your body's clock out of sync with the cycle of light and dark. It can also make it hard to get out of bed in the morning and may bring other problems, too. Teenagers are put in a kind of a gray cloud when they don't get enough sleep, says Mary Carskadon, a sleep researcher at Brown University in Providence, RI7. It affects their mood and their ability to think and learn.

But just like your alarm clock, your internal clock can be reset. In fact, it automatically resets itself every day. How? By using the light it gets through your eyes.

Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal clocks. For years, researchers thought that the signals that synchronize the body's clock were handled through the same pathways that we use to see.

But recent discoveries show that the human eye has two separate light-sensing systems. One system allows us to see. The second system tells our body whether it's day or night.

The clock located inside our brains is similar to our bedside alarm clock because

A. it controls when we wake, when we eat and when we sleep

B. it has a cycle of 24 hours

C. it is a cycle also called circadian rhythm

D. it can alarm any time during 24 hours

参考答案:B 系统解析:【题 干】我们大脑中的生物钟与闹钟相似，因为__________。

A.它控制我们吃饭、睡觉、清醒

B.它有24小时循环

c.这叫做昼夜节奏的循环

D.它在24小时内可以在任何时候发出警告

【解 析】细节题。用句中的your internal clock定位(即指a clock located inside our brains)，第一段第二句提供了答案。

32

What is implied in the second paragraph?

A. Young children's biological clock has the same rhythm with that of the teenagers.

B. People after puberty begin to go to bed earlier due to the change of the biological clock.

C. Children before puberty tend to fall asleep earlier at night than adolescents.

D. Teenagers go to bed later than they used to due to the light from the computer screen.

参考答案:C 系统解析:【题 干】第二段暗含的意思是什么?

A.小孩子的生物钟与十来岁的青少年节奏是一样的。

B.青春期后的人因为生物钟的变化会早一些上床睡觉。

C.未到青春期的孩子往往会比青少年更早入睡。

D.十来岁的青少年由于受到电脑屏幕光线的干扰比往常晚一些睡觉。

【解 析】推理题。第二段主要内容是告诉读者，过了青春期(puberty)，由于生物钟节奏的变化，青少年(adolescents and teenagers)比以前要晚睡几小时，所以C是该段所隐含的内容。

33

In the third paragraph the author wants to tell the reader that

A. it is natural for teenagers to stay up late and get up late

B. staying up late has a bad effect on teenagers' ability to think and learn

C. during puberty most teenagers experience a kind of gray cloud

D. it is hard for teenagers to get out of bed in the morning

参考答案:B 系统解析:【题 干】第三段作者想告诉读者__________。

A.青少年晚睡晚起是很自然的

B.熬夜对青少年的思考和学习能力有不好的影响

C.大多数青春期的少年会经历一种灰色的云

D.早晨青少年起床是很困难的事情

【解 析】细节题。第三段在分析熬夜如何对青少年产生影响，最后一句直接给出了答案：会影响学习和思考的能力。故本题选B。

34

Which of the following statements is NOT true according to the fourth and fifth paragraphs?

A. Our biological clock resets itself automatically.

B. Light gets through our eyes and resets our biological clock.

C. Our internal clock as well as the alarm clock can be reset automatically.

D. Our internal clock, like the alarm clock, can be reset.

参考答案:C 系统解析:【题 于】根据第四段和第五段的内容，下列哪一个不是正确的?

A.我们的生物钟会自动重新设置。

B.灯光会通过我们的眼睛，并重新设置我们的生物钟。

C.我们内置的钟和闹钟一样，都可以自动重新设置。

D.我们内置的钟，像闹钟一样，能被重新设置。

【解 析】细节题。根据第四和第五段的内容，闹钟和生物钟都可以重新设定时间，但生物钟能通过眼睛接受的日光来自动调节生理节奏。所以A、B和D都是这两段中所述内容，C是正确选择，因为闹钟不能自动重新设定时间。

35

According to the last two paragraphs, what did the previous researchers think about the human eye's light-sensing system?

A. The human eye had two light-sensing systems.

B. The human eye had one light-sensing system.

C. The human eye could sense the light of day more quickly than the dark of night.

D. The human eye could reset our internal clocks in accordance with the alarm clocks.

参考答案:B 系统解析:【题 干】根据最后两段，以前的研究者如何看待人类眼睛的感光系统?

A.人类眼睛有两套感光系统。

B.人类眼睛有一个感光系统。

C.比起夜晚的光线，人类眼睛能更快感知到白天的光线。

D.人类眼睛能根据闹钟来重新设置我们体内的生物钟。

【解 析】细节题。问题使用的是过去时，问的是研究者在最新发现(recent discoveries)之前对眼睛感光系统的认识，即，the signals that synchronize the body’S clock were handled through the same pathways that we use to see(眼睛所接受到的平衡生物钟的光信号同样作用于人类的视觉系统)，也就是说，研究者之前认为人类的眼睛只有一个感光系统。但最新发现却是，人的眼睛有两个感光系统。

（责任编辑：pgl）