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问题 选择题

在下列血管中，血液含氧浓度最大的是

A．肺动脉

B．肺部毛细血管

C．肺静脉

D．脑静脉

答案

答案：C

题目分析：A、肺动脉中流的是静脉血，把全身组织细胞产生的二氧化碳带到肺部，静脉血含氧较少，B、肺部毛细血管内的血液是静脉血，含较多的二氧化碳，D、脑属于器官，血液流经脑部要消耗掉大量的氧气，产生二氧化碳，因此流经脑的脑静脉中流的是含氧量低的静脉血，故A、B、D不符合题意。

C、肺是呼吸的主要器官，是气体交换的场所，血液流经肺部，刚通过肺获得氧气，排出二氧化碳，因此肺静脉中流的是动脉血，含氧量高，符合题意。

点评：此题为基础题，难度一般，解答此题的关键是熟练掌握动脉血和静脉血的特点、区别。

选择题

—What's your father?          

— ____.         [ ]

A. He's working in Fukang.         

B. He is always kind to others.         

C. He is really a good man.         

D. He's an engineer.

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填空题

Part 2


Questions 9-18


·Read the following article and answer questions 9-18 on the next page.

Train Your Body into Knowing When It’s Time to Sleep


1. A good night’s sleep actually starts in the morning. The second your eyes open, light shoots down the optic nerve and into the brain’s biological clock. There it stimulates the production of hormones that regulate growth, reproduction, eating, sleeping, thinking, remembering—even how you feel from minute to minute. "Sunlight activates the brain," says Frisca L. Yan-Go, M.D., medical director of the UCLA Sleep Disorders Center. And activating it at the same time every morning synchronizes your body’s biological clock. Then your body has a clear direction that at midnight it’s supposed to be asleep and at noon it’s supposed to be awake. Wake up at a different time every day and the clock is out of order. You feel sleepy and hung over for hours, and even when you start to feel a bit more alert after that first Starbucks (星巴克) , you really never achieve the mental edge of what you’re capable.
2. Shall we go to bed when feeling tired No, not just tired. Sleepy, as your eyes are tired and you keep losing track of what people are saying to you.
3. Sleeping from 11:30 P.M. until 2:00
  • A.M., tossing and tuning until 4, then sleeping until 6 gives you eight hours in bed but only four and a half hours of sleep. That’s a huge mismatch that can actually inhibit your sleep drive and cause insomnia all by itself. To prevent that from worsening your sleep issues, when you wake at 2:00A.M., get up and go to read a book in the living room. Being up increases your sleep drive—which just could make you sleepy enough to actually fall asleep when you return to bed. Caution: Don’t stay in bed when you’re awake. A part of your mind will begin to associate the bed with being awake rather than being asleep. And that can turn on a nasty "I’m-not-going-to-sleep!" anxiety that will speed up your engines whenever you get into bed. It’s one of the causes of chronic insomnia.
    4. You need one hour before bed to wind down and get transition from the woman-who-can-do-everything into the woman-who-can-sleep. Unfortunately, most women are not giving themselves one single second. According to the 2007 National Sleep Foundation poll, during the hour before bed, around 60 percent of us do household chores, 37 percent take care of children, 36 percent do activities with other family members, 36 percent are on the Internet, and 21 percent do work related to their jobs.
    5. Staying up late on Friday and Saturday nights and getting up late on Saturday and Sunday mornings is frequently the gift we give ourselves on weekends after a hard week at work. Yet that little gift—small as it is—is enough to screw up our biological clocks. Even if you get to bed early on Sunday night, you will not be ready to sleep, and you will not end up being the happy camper Monday morning.

    Questions 9-13


    ·For questions 9-13, choose from the list A-G which best summarize each part of the article.
    ·For each numberedparagraph (1-5), mark on letter (A-G) on the Answer Sheet.
    ·Do not mark any letter twice.A. Do household chores before bed
  • B. Hit the sheets only when sleepy
  • C. Stay up late only on Saturday nights
  • D. Give yourself an hour before bed
  • E. Wake up at the same time every day
  • F. Beware of Sunday night insomnia
  • G. Get up when awake

Paragraph 5 ______
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