下列哪种糖构成RNA?() A.蔗糖 B.果糖 C.核糖 D.乳糖 E.葡萄糖

题型:单项选择题 A1/A2型题

问题:

下列哪种糖构成RNA?()

A.蔗糖

B.果糖

C.核糖

D.乳糖

E.葡萄糖

考点:营养(士)蛋白质蛋白质题库
题型:单项选择题 A1/A2型题
在△ABC中,角A,B,C所对的边长分别是a,b,c.
(1)若sinC+sin(B-A)=sin2A,试判断△ABC的形状;
(2)若△ABC的面积S=3
3
,且c=
13
,C=
π
3
,求a,b的值.
题型:单项选择题 A1/A2型题

更年期妇女内分泌变化主要表现为

A.FSH升高,LH水平增高;雌激素水平与孕激素水平下降

B.FSH、LH水平下降,雌、孕激素水平升高

C.FSH水平升高,LH水平下降,雌、孕激素水平不变

D.FSH水平下降,LH水平升高,雌、孕激素水平升高

E.FSH水平不变,LH水平升高,雌、孕激素水平升高

题型:单项选择题 A1/A2型题

Culture helps human societies survive in changing natural environment.For example, the end of the last Ice Age, beginning about 15,000 years ago, brought a big challenge to which humans had to adapt.Before this time, large parts of the northern hemisphere were covered in great sheets of ice that contained much of the earth' s water.In North America, large animals that wandered the vast tundra (冰原) provided people with food and materials for clothing and simple shelters.When the earth became warm, large Ice Age animals disappeared, and many land areas were covered by rising sea levels from melting ice.But people survived, they developed new technologies and learned how to survive on new plant and animal species. Finally some people settled into permanent villages, durable houses and farms.

Cultural adaptation has made humans one of the most successful species on the planet. Through history, major developments in technology, medicine, and nutrition have allowed people to reproduce and survive in ever-increasing numbers.The global population has risen from 8 million during the Ice Age to about 6 billion today.

However, the successes of culture adaptation can also create problems in the long run.Over the last 200 years, people have begun to use large quantities of natural resources and energy and to produce a great amount of material and chemical wastes.The global population now consumes some important natural resources—such as petroleum, wood, and minerals—faster than nature can produce them.Many scientists believe that in the process of burning fuels and producing wastes, people may be changing the global climate in unpredictable and possibly harmful ways.Thus, the adaptive success of the present-day global culture of production and trade may be temporary.

小题1:What is the first paragraph mainly talking about?

A.How the human beings survived in the Ice Age.

B.What the situation was like during the Ice Age.

C.What caused the Ice Age to come to an end.

D.Why the Ice Age was very important.小题2:To deal with the problems, human beings should ______according to the passage.

A.stop developing any longer

B.reduce the overuse of natural resources

C.stop the global warming and using natural resources

D.save more animals in case they all die out小题3:Which of the following is the problem caused by cultural adaptation according to the passage?

A.A very developed culture came into being.

B.New technologies have been developed.

C.Natural resources have been used up.

D.Human activities have done damage to the balance of nature.小题4:Which of the following can be the best tide of the passage?

A.Natural Environment Should Be Protected.

B.The Success of Cultural Adaptation Is Not Permanent.

C.The Global Population Is Increasing Since Ice Age.

D.Human Beings Are Capable of Surviving on Earth.

题型:单项选择题 A1/A2型题

银行在银行结算账户的开立过程中,违反规定为存款人多头开立银行结算账户的,给予警告,并处以5万元以上10万元以下的罚款。()

题型:单项选择题 A1/A2型题

免费版139邮箱的短信开通方式:(),短信取消方式:(),月功能费(),邮箱容量(),最大附件容量()。

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