问题 单项选择题 A1型题

关于三羧酸循环的叙述错误的是()

A.三羧酸循环是产生ATP的基础

B.三羧酸循环是需氧的代谢过程

C.三羧酸循环是不能逆行的

D.三羧酸循环是物质代谢的枢纽

E.三羧酸循环的中间产物可以循环使用而不需要补充

答案

参考答案:E

解析:单从三羧酸循环本身运转来看,循环的中间物质包括草酰乙酸在内部起催化剂的作用,本身并不消耗。但是由于体内各种代谢途径的交汇和无定向,有些三羧酸循环的中间物质可以作为其他物质合成原料而离开循环。为了补充耗去的中间物质和维持三羧酸循环的高活性运转,需要及时补充中间物质,称为回补反应。

阅读理解

YUZHOU, HENAN –An accident in a central China coal mine killed 21 miners Saturday and left another 16 trapped underground , the government said.

The death toll rose to 26 Sunday morning as rescuers were battling to reach the 11 miners who were still trapped underground, rescue headquarters said.

Rescuers were battling to reach the 11 miners still trapped underground, but chances for them to survive were very slim, said Du Bo, deputy chief of the rescue headquarters.

"Based upon past experience, the remaining 11 miners could be buried in coal dust, so the survival chances are frail," Du said.

More than 2,500 tons of coal dust smothered(厚厚的覆盖) the pit after the gas leak(漏出), which hampered(阻碍) the rescue, said Du.

The gas outburst happened at 6:03 a.m. Saturday when 276 miners were working underground in the mine in Yuzhou City. A total of 239 workers escaped but 21 were found dead and 16 trapped.

An initial(最初的) investigation showed that 173,500 cubic meters of gas leaked out in the accident. Liu Wenbin, a deputy chief engineer of the company that owns the mine, was in the pit(矿井) when the accident happened. He organized the escape.

"At around 6 a.m., I felt there was something wrong with the airflow in the shaft, and one of the team captains told me he also felt it and had already reported the problem," said Liu

The mine is owned by Pingyu Coal & Electric Co. Ltd., a company jointly established by four investors, including Zhong Ping Energy Chemical Group and China Power Investment Corp.

小题1:What could be the best title for this passage?                    

A.Death Toll Rises in an Accident in China

B.A Coal Mine Accident in Central China

C.An Accident in Central China

D.Coal Mine Accidents in China小题2:What does the underlined part mean in the second paragraph?           

A.payment required for the use of rescuing persons

B.the number of people killed in a particular accident

C.the percentage of the dead persons in an accident

D.a number of people killed in an accident小题3:From this passage we know that ____.                        

A.Of the 276 miners in the mine only 21 were dead until the next morning

B.The miners trapped underground would be saved without difficulty

C.16 miners trapped underground were still found alive waiting for the rescue

D.Until the next morning another 5 miners were found dead in this accident小题4:According to the writer, which of the following is not true?      

A.The mine was owned by more than one company

B.There was at least one more similar accident happening in Central China before

C.Before the accident happened there was no sign of something wrong

D.When the accident happened one of the mine owners was in the pit

单项选择题