试题与答案

—She looks . — Yes, because she has a va

题型:选择题

题目:

— She looks     .

—  Yes, because she has a      vacation.

A.relaxed,relaxed

B.relaxing,relaxed

C.relaxed,relaxing

D.relax,relaxing

答案:

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下面是错误答案,用来干扰机器的。

(1)3He、4He两种原子的质子数相同,中子数不同,所以相对原子质量不同.故填:中子.(2)天然气的主要成分是甲烷.故填:甲烷.甲烷燃烧的化学方程式为:CH4+2O2 点燃..CO2+2H2O.(3)丁烷的沸点是-0.5℃,...

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题型:阅读理解与欣赏

智慧也可以移植

王金宝

       ①《聊斋志异》中有这样一段故事:读书人朱尔旦天生愚笨,学习成绩很糟,几次参加科考都未及第。后来,他结识了一位主管人间生死的陆判官,请求帮忙。陆判官施展法术,从死人身上选了一颗“慧心”,调换给了朱尔旦。从此朱尔旦变得非常聪明,读书过目不忘,下笔神思飞扬,不久就考中了举人。这个故事虽说是蒲松龄先生编造的,但现代科学不仅有可能用生物工程方法把知识“拷贝”到大脑里,使一个知识不多的人很快获得很高的常识,而且有可能将人的智慧从一个人的身上搬到另一个人身上,使后者拥有前者的记忆。

       ②早在60年代,美国心理学家麦康纳尔就用涡虫做过记忆移植的实验。他用一束光去照射一群涡虫,同时用电流刺激它们。时间久了,这群涡虫就形成了一种条件反射,一看到光束,即使没有电流也会马上避开。麦康纳尔把这些涡虫碾成了浆液,用来喂没有训练过的涡虫。奇迹发生了,没有经过训练的涡虫看到光束也马上避开了。这个实验表明,动物的记忆可能存在于某种物质之中,因而可以从一个个体移植给另一个个体。

       ③1978年,联邦德国有位生物学家叫马田,他做了一个有趣的实验,来证实麦康纳尔的结论。马田选择了两只健康的蜜蜂,对其中的一只作专门训练,每天让它在一个固定的时刻从蜂房里飞到另一个蜂房去寻找一碗糖蜜。时间久了,这只蜜蜂就养成了每天在固定的时间作一次这种飞行的习惯。马田从被训练过的蜜蜂的神经组织里取出某些物质,移植到未训练过的蜜蜂的神经组织里。奇迹出现了,未训练过的蜜蜂的伤口长好后,居然像训练过的蜜蜂一样,每天到了固定时间,就毫不迟疑地飞到放着糖蜜的那个蜂房里去。

       ④马田的“换脑术”轰动了欧洲,那些持怀疑态度的人也不得不相信,记忆是完全可以移植的。

       ⑤美国的神经化学家瓦加尔,曾从大鼠的脑中分离出了3种记忆物质,它们是黑暗恐惧素、嗓声忍受素、蓝绿色辨别素。把这3种物质中的一种注入大鼠的脑中,大鼠就能增加对某一方面的感受能力。荷兰化学家戴维德从大鼠脑中分离出另外一种记忆物质,把这种物质注射到大鼠的脑中,大鼠的记忆力就显著提高。

       ⑥到目前为止,从高等动物中分离出来的记忆物质还不很多。经分析发现,这些记忆物质都是由某种特殊的蛋白质组成,因为构成的形式不一样,性质也就大不一样。

       ⑦瓦加尔进一步预言:记忆也像动物的遗传那样,是通过一种密码来实现的,一切动物的记忆密码都相同。

       ⑧既然记忆的化学本质是蛋白质,那么记忆蛋白能否应用于人类呢?为此比利时科学家进行了大胆的实验:他们用加压素喷洒一位因车祸昏迷不醒的青年的鼻子,一天后这位青年记起了一些车祸的情况,一星期后恢复了记忆。以后他们发现加压素不仅能恢复病人的记忆,而且能提高记忆力、识别力和注意力。

       ⑨记忆移植的研究正在逐步深入,一旦获得成功,《聊斋志异》中的神话将变成现实,科学技术和社会生活将发生新的飞跃。假如有一个伟大的科学家即将离世,只要把他大脑中的记忆物质取出来,移植到一些年轻科学家的头脑里,他的工作就可以有人接替了。 (本文摘选自《中国科协报》)

1、开头一段的故事有什么作用?

  _________________________________________________________________________________________

2、将第②段分为两层,并说明划分的理由。

  _________________________________________________________________________________________

3、文中②—⑥段大致是按什么顺序来进行说明的?

  _________________________________________________________________________________________

4、从文中找出两个用词准确、严密的句子,在有关词语下面打上着重号。

  _________________________________________________________________________________________

5、文中用得最多的一种说明方法是_____________________

6、全文的结构方式是_______________________

7、文中是怎样说明“记忆移植的研究正在逐步深入”的?

  _________________________________________________________________________________________

8、全文说明的是移植“记忆”,可标题却是移植“智慧”,这个标题有问题吗?为什么?

  _________________________________________________________________________________________

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题型:单项选择题

Wherever people have been, they have left waste behind, which can cause all sorts of problems. Waste often stinks, attracts vermin and creates eyesores. More seriously, it can release harmful chemicals into the soil and water when dumped, or into the air when burned. And then there are some really nasty forms of industrial waste, such as spent nuclear fuel, for which no universally accepted disposal methods’ have thus far been developed.

Yet many also see waste as an opportunity. Getting rid of it all has become a huge global business. Rich countries spend some $120 billion a year disposing of their municipal waste alone and another $150 billion on industrial waste. The amount of waste that countries produce tends to grow in tandem with their economies, and especially with the rate of urbanization. So waste firms see a rich future in places such as China, India and Brazil, which at present spend only about $5 billion a year collecting and treating their municipal waste.

Waste also presents an opportunity in a grander sense: as a potential resource. Much of it is already burned to generate energy. Clever new technologies to turn it into fertiliser or chemicals or fuel are being developed all the time. Visionaries see a world without waste, with rubbish being routinely recycled.

Until last summer such views were spreading quickly. But since then plummeting prices for virgin paper, plastic and fuels, and hence also for the waste that substitutes for them, have put an end to such visions. Many of the recycling firms that had argued rubbish was on the way out now say that unless they are given financial help, they themselves will disappear.

Subsidies are a bad idea. Governments have a role to play in the business of waste management, but it is a regulatory and supervisory one. They should oblige people who create waste to clean up after themselves and ideally ensure that the price of any product reflects the cost of disposing of it safely. That would help to signal which items are hardest to get rid of, giving consumers an incentive to buy goods that create less waste in the first place.

That may sound simple enough, but governments seldom get the rules right. In poorer countries they often have no rules at all, or if they have them they fail to enforce them. In rich countries they are often inconsistent: too strict about some sorts of waste and worryingly lax about others. They are also prone to imposing arbitrary targets and taxes. California, for example, wants to recycle all its trash not because it necessarily makes environmental or economic sense but because the goal of “zero waste” sounds politically attractive.

Which of the following is true according to the last paragraph()

A. Rich countries might help poor countries to treat the waste

B. California’s “zero waste” program makes no environmental sense

C. More taxes are needed to collect and treat the waste efficiently

D. Governments’ policies on waste industry are largely incoherent

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