Passage Five
The immune system is the body’s defender. It identifies, tracks down, and destroys troublemakers before they can hurt the body. Those troublemakers maybe, for example, bacteria from a cut or splinter, a measles germ, a cold bug, or even a cancer cell.
These invaders try to take over our tissues and feed off our bodies’ nutrients. If they succeed, we become sick or, sometimes, even die. It’s the job of our immune systems to destr oy these invaders before they destroy us.
Say you picked up a flu virus last week. Perhaps it entered your body through a cut, from a drinking glass, or from the air you breathe. Of course, you didn’t feel it, but the virus made its way into your bloodstream. As soon as it entered your body, it began to reproduce. Viruses have only one goal: to take over your cells. Once inside your body, viruses try to enter cells and disrupt their normal work. If left alone, these viruses would hurt so many cells that you would weaken, or worse, get a serious disease.
But this flu virus should not be so complacent as it seems to be. As it reproduces in your bloodstream, the virus is met by a certain kind of white blood cell, the lymphocytes. The lymphocytes are the foot soldiers that keep you alive.
The number of lymphocytes in your body is hard to imagine. Thousands of them could fit in the period at the end of this sentence. Your body holds about a trillion—that’s 1, 000, 000, 000, 000 of them, or about 3, 000 in every drop of blood. Since you began reading this sentence, over 800, 000 of them have been created and destroyed.
Some of these lymphocytes pass through a small walnut-sized organ called the thymus. The thymus is the base of the neck. Here, special hormones turn lymphocytes into fighting cells, called T cells.
T cells have one terrific talent:they can tell the difference between friend and foe;what should be in our bodies and what shouldn’t. They do not affect the body’s
healthy cells. Yet they attack everything that is foreign to our bodies, such germs, transplants, and even our own cells which have become abnormal, as in the case of cancer.
21. What is the function of our immune system?
A. To take over our tissues and feed off our bodies’nutrients. B. To prevent bacteria or germs from entering the body.
C. To destroy the troublemakers in order that they might not hurt the body. D. To fight against T cells.
22. What does the word “lymphocytes” in Para.4 mean? A. Foot soldiers. B. Flu virus. C. White blood cells. D. Trouble makers.
23. The last sentence in Para.5 “Since you began reading this sentence, over 800, 000 of them have been created and destroyed” implies that .
A. this sentence contributes to the increase of the number of lymphocytes in your body
B. you would not realize that lymphocytes reproduce themselves rapidly but for this sentence
C. because you read this sentence, a large number of lymphocytes have been consumed
D. the number of lymphocytes in your body is extremely large 24. Which of the following questions can NOT be detected by T cells? A. Thymus. B. Transplants. C. Cancer cells. D. Healthy cells.
25. Which of the following questions best summaries the main idea of the whole passage?
A. How does the immune system attack the flu virus? B. How does the immune system function in our body? C. How do the lymphocytes work in our body? D. What is the so-called immune system? Passage Six
Very old people do raise moral problems for almost everyone who comes into contact with them. Their values-this can't be repeated too often-are not necessarily our values. Physical comfort,cleanness and order are not necessarily the most important things. The social services from time to ti me find themselves faced with a flat with decaying(腐烂food covered by small worms,and an old person lying alone on bed,taking no notice of the worms. But is it interfering with personal freedom to insist that they go to live with some of their relatives so that they might be taken better care of? Some social workers, the ones who clear up the worms,think we are in danger of carrying this concept
of personal freedom to the point where serious risks are being taken with the health and safety of the old.
Indeed,the old can be easily hurt or harmed. The body is like a car: it needs more mechanical maintenance as it gets older. You can carry this comparison right through to the provision of spare parts. But never forget that such operations are painful
experiences,however good the results. And at what point should you cease to treat the old body? Is it morally right to try to push off death by continuing the development of drugs to excite the forgetful old mind and to make the old body active, knowing that it is designed to die? You cannot ask doctors or scientists to decide,because so long as they can see the technical opportunities, they will feel bound to give them a try, on the principle that while there is life,there is hope.
When you talk to the old people, however, you are forced to the conclusion that whether age is happy or unpleasant depends less on money or on health than it does on your ability to have fun.
26. It is implied in Para. 1 that _________. A. very old people enjoy living with their relatives B. social services have nothing to do with very old people
C. very old people would like to live alone so that they can have more personal freedom
D. very old people are able to keep their rooms very clean 27. Some social workers think that _________.
A. health and safety are more important than personal freedom B. personal freedom is more important than health and safety
C. old people should keep their rooms clean D. one should not take risks dealing with old people 28. In the author's opinion, _________. A. the human body can't be compared to a car B. the older a person,the more care he needs
C. too much emphasis has been put on old people’s values D. it is easy to provide spare parts for old people
29. The word “it” in the last paragraph refers to _________. A. the conclusion you have come to B. whether age is happy or unpleasant C. your talk to the old people D. one’s money or one’s health 30. The author thinks that _________.
A. medical decisions for old people should be left to the doctors B. old people can enjoy a happy life only if they are very rich
C. the opinion that we should try every means possible to save old people is doubtful D. it is always morally right to treat old people and push off death 答案解析 Passage Five
2013年同等学力英语阅读理解练习题精选.
