噬菌体、大肠杆菌、水稻和青蛙等生物体结构或细胞中都具有的糖是[ ] A.脱氧核糖

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问题:

噬菌体、大肠杆菌、水稻和青蛙等生物体结构或细胞中都具有的糖是[ ]

A.脱氧核糖

B.纤维素

C.肌糖原

D.乳糖

考点:DNA
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杨宏同学根据课本中的“试一试”用易拉罐做小孔成像实验:

(1)请在图中画出蜡烛AB的像A’B’.

(2)杨光发现蜡烛和小孔的位置固定后,像离小孔越远,像就越大.他测出了不同距离时像的高度,填在下表中:

请你根据表中的数据在图中的坐标系中画出h和s的关系图象.

(3)从图象中可以看出像的高度随像到小孔的距离的变化规律为:______.

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提出“百病兼痰”的著名观点的医学家是()

A.刘完素

B.朱丹溪

C.李杲

D.张从正

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市场顾客是可以被创造出来的。

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Many people are surprised when they find the Internet(因特网)was set up in the 1960s. At that time, computers were large and expensive. Computer networks(网络) didn’t work well. If one computer in the network broke down, then the whole network stopped. So a new network system (系统) had to be set up. It should be good enough to be used by many different computers. If a part of the network was not working, information could be sent through another part. In this way computer network system would keep on working all the time.
At first the Internet was only used by the government, but in the early 1970s,universities(大学) ,hospitals and banks were allowed(允许) to use it too. However, computers were still very expensive and the Internet was difficult to use. By the start of the 1990s, computers became cheaper and easier to use.
Today it is easy to get on-line(上网) and it is said that millions of people use the Internet every day. Sending e-mail is more and more popular among students.
The Internet has now become one of the most important parts of people’s life.

At first computer networks ______.

A. worked quite well
B. were very popular
C. went wrong easily

题型:选择题

从进近方向看,PAPI一般装在跑道的:().

A.两边

B.中间

C.左边

D.右边

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