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问题 选择题

2011年7月11 日是第二十二个世界人口日，今年世界人口日的主题是“面对70亿人的世界”。70亿人口背景下的中国现实：积极应对老龄化（下图），为此我们要[ ]

①大力培养人们的创新精神                  

②加强社会保障制度建设  

③坚持实行计划生育的基本国策  

④弘扬尊老爱老观念      

A．①③④                                

B．①②③  

C．①②④                        

D．②③④

答案

答案：D

单项选择题

Air pollution is caused by many things. Great clouds of smoke come from factories. Cars send smoke and fumes into the air. Burning waste fills the air with bits of dirt. Even burning leaves add smoke to the air. Sometimes, planes cannot find their landing spots through smoke. Smoke of all kinds is bad to breathe and can do great harm to the body.
Still, we cannot live without air. We must find a way to clean the air we have.
In time, we may have factories that are run by atomic energy. Our cars may run on smoke-free electric power. Scientists are also working on new ways to help the oil burned by cars from making fumes. Waste may be burned in the sand on ocean floors.
These changes might keep our air clean in the years to come. But until then, many scientists are looking for ways to make air cleaner now.

Scientists are now working on ways to ______.

A. keep planes from :flying
B. bury sand on ocean floors
C. stop air pollution
D. burn leaves without smoke
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单项选择题

下图是人体内糖代谢过程的简图，请分析以下叙述错误的是（）

A.如果图示的细胞是肝细胞，则图示中A所示的物质最可能是肝糖元

B.如果图示的细胞是肌细胞，则该细胞不具备细胞周期

C.图示中的④过程会使细胞中ADP的含量上升

D.如果人体内甲状腺激素浓度过高，则图中②的过程将加快
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