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问题 选择题

人体新个体的产生要经历受精过程及胚胎发育形成新个体的过程．其中，受精过程是指（　　）

A．受精卵进入子宫的过程

B．产生精子和卵细胞的过程

C．精子进入输卵管的过程

D．精子和卵细胞结合的过程

答案

通过对这部分知识的学习知道人的受精过程是指精子与卵细胞结合形成受精卵的过程．

A、受精卵进入子宫时受精过程已经完成，不是人的受精过程．

B、产生精子和卵细胞的过程是产生生殖细胞的过程，不能形成受精卵，所以不是受精过程．

C、精子进入输卵管，是精子到达了受精部位，不是受精过程．

D、精子与卵细胞结合的过程，就形成了受精卵．故符合题意．

故选：D．

不定项选择

在磁感应强度为B、方向竖直向上的匀强磁场中，水平放置一根通电直导线，电流力方向垂直于纸面向里，如图所示，a、b、c、d是以直导线为圆心的同一圆周上的四点，则

[ ]

A．c、d两点的磁感应强度大小相等

B．a、b两点的磁感应强度大小相等

C．c点的磁感应强度的值最小

D．b点的磁感应强度的值最大

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填空题

It has often been remarked that the saddest thing about youth is that it is wasted on the young. Reading a recent newspaper report on a survey conducted among college freshmen, I recalled the regret,
"If only I knew then what I know now."
The survey disclosed what I had already suspected from informal polls of students. According to the survey, which was based on the responses of over 188,000 students, today’s traditional-age college freshmen are" more materialistic and less altruistic".
41. ______. It follows then that today the most popular course is not literature or history but accounting. Interest in teaching, social service and the" altruistic" fields is at a low, along with ethnic and women’s studies. On the other hand, enrollment in business programs, engineering and computer science is way up.
42. ______.
Frankly, I’m proud of the young lady (not her attitude but her success). But why can’t we have it both ways Can’t we educate people for life as well as for a career I believe we can. If we’re not, then that is a fault of our educational system--elementary, secondary and higher. In a time of increasing specialization, a time when 90 percent of all the scientists who have ever lived are currently alive, more than ever we need to know what is truly important in life.
43. ______.
Most of us finally come to realize that quality of life is not entirely determined by how much we earn. Sure, everyone wants to be financially comfortable, but we also want to feel that we have a perspective on the world beyond the confines of our occupation; we want to be able to render service to our fellow man and to the world.
44. ______.
It is equally true that, in studying the diverse wisdom of others, we learn how to think. More important, perhaps, education teaches us to see the connections between things, as well as to see beyond our immediate needs.
45. ______.
In the long run that’s what education really ought to be about. And I think it can be. That’s the way it should be. Oscar Wilde had it right when he said that we ought to give our ability to our work but our genius to our lives. Let’s hope our educators answer the students cries for career education, but at the same time, let’s ensure that the students are prepared for the day when they realize their folly. There’s a lot more to life than a job.
[A] Academic emphasis on competition, rationality and externals acknowledges only one kind of knowing. It makes students devalue their inner selves or larger social purposes.
[B] Not surprising in these hard times, the student’s major objective" is to be financially well off." Less important than ever is developing a meaningful philosophy of life.
[C] Education must meet the needs of the human spirit. It must assist students to develop a satisfactory personal philosophy and sense of values; to cultivate tastes for literature, music and the arts; to grow in ability to analyze problems and arrive at thoughtful conclusions.
[D] That’s no surprise either. A friend of mine (a sales representative for a chemical company)was making twice the salary of her college instructors during her first year on the job. And that was four years ago; She must be earning much more now.
[E] Most people, somewhere between the ages of 30 and 50, finally arrive at the inevitable conclusion that they could do more than serving a corporation, a government agency, or whatever.
[F] But the most important argument for a broad education is that in studying the accumulated wisdom of the ages, we improve our moral sense.
[G] While it’s true that we all need a career, preferably a profitable one, it is equally true that our civilization has accumulated an incredible amount of knowledge -- be it scientific or artistic.
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