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【单选题】
In the earliest stages of man’s development he had no more need of money than animals have. He was content with very simple forms of shelter from natural materials around him. he made his own rough tools and weapons. As he became more civilized, however, he began to want better shelter, more efficient tools and weapons, and more comfortable clothing than could be provided by the work of his own unskilled hands. For these things he had to turn to the skilled people such as smiths and carpenters who were springing up everywhere. It was then that the question of payment arose At first he got what he wanted by a simple process of exchange. The smith who had not the time to look after land or cattle was glad to take meat or grain from the farmer in exchange for an axe or a plough. But as more and more goods which had no fixed exchange value came on the market, exchange became too complicated to be satisfactory. Another problem arose when those who made things wanted to get stocks of wood leather, or iron, but had nothing to offer in exchange until their finished goods were ready. Thus the difficulties of exchange led by degrees to the invention of money. In some countries, easily handled things like seeds or shells were given a certain value and the farmer, instead of paying the smith for a new axe by giving him some meat or grain, gave him so many shells. If the smith had any shells left when he had bought his food, he could get stocks of the raw materials of his trade. In some countries quite large things such as cows or camels or even big flat stones were used for trade. Later, pieces of metal, bearing values according to the rarity of the metal and the size of the pieces, or coins were used. Money as we know it had arrived. 1:What does the first paragraph mainly tell us?
A.
Man needed little in the earliest stages of development
B.
Man preferred to make tools by himself.
C.
How the simple process of exchange arose.
D.
What the early man needed from others
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【单选题】Your hair and eyes _____ me _____ your mother.
A.
pack...up
B.
be thankful ... for
C.
remind... of
D.
look ... up
【判断题】古希腊历史中的荷马时期具体指的是公元前750年到公元6世纪末。()
A.
正确
B.
错误
【简答题】DNA(deoxyribonucleic acid)又称脱氧核糖核酸,它是一种高分子化合物,组成单位为四种脱氧核苷酸,即:____、____、____、____。
【单选题】用于基本生产车间照明用电,应记入( )
A.
管理费用
B.
制造费用
C.
基本生产成本
D.
辅助生产成本
【简答题】核酸分为两类,即脱氧核糖核酸(DNA)和核糖核酸(RNA)。DNA的碱基包括____________,RNA的碱基包括___________。
【单选题】生物学上有一个轰动世界的发现,就是可以把遗传的信息挂在一个叫去氧核糖酸即DNA的高分子化合物的某一段上传下去。这就是把这种高分子人为地变化一下,把一个高分子的某一段遗传信息切下来,接到另一个上面,改变遗传的某一特性或创造新的物种。这样,就有可能打破植物、动物的界限,把植物的某一特性接到动物上面。这样,不但能使细胞内部发生变化,而且使细菌发生变化,如把胰岛素的遗传信息切下来,接到容易繁殖的大肠杆菌上...
A.
遗传工程是把遗传信息挂在DNA某一段上传下去的一门技术
B.
遗传工程是把DNA某一段遗传信息切下来接到另一个上面的一门技术
C.
遗传工程是把植物某一特性接到动物上面的一门技术
D.
遗传工程是人为变化DNA以改变遗传某一特性或创造新物种的一门技术。
【单选题】Your hair and eyes____ me of your mother.
A.
remind
B.
blame
C.
share
D.
Gain
【单选题】Your hair and eyes _____ me _____ your mother.
A.
pack...up
B.
remind...of
C.
be thankful...for
D.
look up for...in
【判断题】脱氧核糖核酸,即DNA,大多位于细胞核内,其功能主要为携带遗传信息。
A.
正确
B.
错误
【判断题】公元前750年到公元6世纪末是古希腊历史中的荷马时期。()
A.
正确
B.
错误
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