在 DNA 聚合酶 III 催化新链合成以前发生了什么反应?

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问题:

在 DNA 聚合酶 III 催化新链合成以前发生了什么反应?

考点:生物学DNA复制DNA复制题库
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成熟的嗜酸性粒细胞主要存在于( )

A.外周血

B.骨髓和组织

C.淋巴结

D.脾

E.胸腺

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给问句选择合适的答语。
( ) 1. What's your father like? 
( ) 2. Can you cook the meals?        
( ) 3. Are there any goats? 
( ) 4. Is there a book in the bag?   
( ) 5. Do you like your English teacher?
A. Yes, there are. 
B. No, there is a pen.                                      
C. No, I can't. 
D. Yes, I do. 
E. He's tall.  
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下列属于个体经济、私营经济和外资经济的共同点的是(    )

A.劳动成果直接归劳动者所有和支配

B.都以雇佣劳动为基础

C.都是社会主义经济的重要组成部分

D.都有利于扩大就业,增加国家税收

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1 There are many arguments for and against television.

The poor quality of its program is often criticized and TV

commercials are also boring. So television is undoubtedly 1.__________

a great comfort to many lonely and elderly people.

2 The manager of a large office building had received

many complains about elevator service in the building,

but he engaged a group of engineers to study the situation 2.__________

and make recommendation for improvement.

3 We asked a lady, who replied that she thought

you could tell a well-mannered person by the way

they occupied the space around them——for example,

when such a person walks down a street he or she is

constantly unaware of others. Such people never 3.__________

bump into other people.

4 Until the very latest moment of his existence,

man has been bound the planet on which he

originated and developed. Now he has the capability

to leave that planet and move out into the universe to

those worlds which he has known previously only directly. 4.__________

5 One major decision which faces the American

students ready to begin higher education is the

choice of attending a large university or a small

college. The large university provides a wide range of

specialized departments as well as numerous courses

within such departments. The small college, therefore, 5.__________

generally provides a limited number of courses

and specializations but offers a better student-faculty

ratio, thus permitting individualized attention to students.

6 Music the Johnny has learned to appreciate as

unpleasant is just dull noise to Jimmy——and quite 6.__________

possible, vice versa.

7 We are learning, finally, that silence is a natural

resource and must be protected by law. It appears

that we all find company in sound, if we all 7.__________

demand a little quiet from time to time.

8 The farmer aroused at down or before it and

had much work to do, with his own muscles as his

chief source of power. He used axes, spades and 8.__________

other complicated tools.

9 Whether women who have started a career

will attain pay equality with men rests on at least

two factors. First, will most of them continue

part-time at their jobs after they have children? A 9.__________

break in their employment, or a decision to work

part-time, will slow their raises and promotions as

it would for men.

10 Whether true or not, the story illustrates the

problem with idioms. They are almost possible to 10.__________

understand from the meanings of the individual

words. And with English idioms, even the same

words may have different meanings.

在4处填写改错内容。

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池塘养殖普遍存在由于饵料、鱼类排泄物、换水不及时等引起的水体污染现象,研究者设计了一种循环水池塘养殖系统(如下图)。请回答下列问题:

该养殖系统设计为前一池塘上层水流入后一池塘底部,实现水层交换,其目的有()、()

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