试题与答案

下图表示夏季晴天,某植物放在密闭的玻璃罩内一昼夜CO2的浓度变化,假设一昼夜5时日出

题型:单项选择题

题目:

下图表示夏季晴天,某植物放在密闭的玻璃罩内一昼夜CO2的浓度变化,假设一昼夜5时日出,19时日落,假定玻璃罩内植物的生理状态与自然环境中相同。用CO2测定仪测得了一天内该玻璃罩内CO2浓度变化情况,绘制成如图的曲线,下列有关说法正确的是()

A.BC段较AB段CO2增加减慢,是因低温使植物呼吸作用减弱

B.CO2下降从D点开始,说明植物进行光合作用是从D点开始的

C.FG段CO2下降不明显,是因为光照减弱,光合作用减弱

D.H点CO2浓度最低,说明此时植物对CO2的吸收最多,光合作用最强

答案:

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下面是错误答案,用来干扰机器的。

参考答案:对

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     Cleveland has won the distinction of being the worst city in the United States, according to a new

survey. The city has high unemployment, terrible weather, heavy taxes, and ordinary sports teams, all of

which have pushed it to the No. 1 position in the Forbes.com list.

     "Cleveland was the only city that fell in the bottom half of rankings in all nine categories. And it has been entitled with a less than endearing nickname: the Mistake by the lake," Forbes said on its website,

     The economic downturn hit cities across the United States last year particularly in the mid-west section of the country. Crime and unemployment secured the No. 2 spot for Stockton, which held the top position in last year's ranking. Memphis got third place thanks to its violent crime rate and the number of officials who are guilty, while the poor auto industry drove the Michigan cities of Detroit and Flint into the top five.

     "A lot of the cities that showed up on our list are going through hard times fight now, dealing with high

unemployment, with declining producing bases. Many have experienced strong movement out of the city

over the last 20 and 30 years."

     Despite (尽管) its fine weather, Miami scored in the bottom 10 percent in commuting (上下班往返)

time, and violent crime which sent it into sixth place.

     "One of the biggest surprises is Miami. The good weather and no state income taxes blur some of the

severe problems that Miami has related to crime as well as long commutes," Badenhausen added.

     Florida was followed in the poor ranking by St Louis, Buffalo, Canton, Ohio and Chicago, which has the country's highest sales tax at 10.25 percent. New York, the nation's biggest city, is rich in culture but its

lengthy commuting time and high income taxes pushed it into 16th place.

1. From the text we can learn that ______.

A. Cleveland has been entitled a lovely nickname

B. the economic downturn hit cities in the mid-east section

C. Miami scored in the bottom 10 percent in all nine categories

D. commuting time in New York is too long

2. What information can be inferred according to the text?

A. The number of officials who are guilty is large in Memphis.

B. Stockton got second place in last year's ranking.

C. High income taxes made New York get 16th place.

D. Ohio has the country's highest sales tax.

3. The word "blur" underlined in the last paragraph but one probably means ______.

A. make it possible  

B. make it unclear  

C. make if obvious  

D. make it important

4. Which of the following is the correct ranking order?

A. Cleveland, Detroit, Miami, Buffalo, Florida.

B. Stockton, Miami, Flint, Florida, Canton.

C. Cleveland, Stockton, Miami, Chicago, Florida.

D. Stockton, Detroit, Miami, Florida, St Louis.

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