题干

科学家在两种二氧化碳浓度和两个温度条件下,研究了不同光强度对黄瓜光合速率的影响,实验结果如图所示,以下相关叙述中不正确的是                                                           (   )

A:从图中曲线可以看出,在温度较高或二氧化碳浓度较高的情况下,光强度对光合速率的影响比较显著

B:从图中曲线可以看出,环境因素中的温度、CO2浓度或光强度的降低都能减弱光合作用

C:从图中曲线变化情况看,无法确定黄瓜光合速率的最适温度

D:从图中曲线可以看出,温度从20℃升高到30℃比二氧化碳从低浓度到高浓度对光合速率的促进作用更显著

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D

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    On 20th July 1969, millions of people saw Neil Armstrong take his first steps in space on television. Armstrong got out of the spacecraft Apollo 11, touched the ground of the moon and said, “That's one small step for man, one giant leap for mankind.”

    A conspiracy(阴谋)theory has existed since the night of his lunar handing. Armstrong's achievements were considered amazing, but people wondered if it really happened. Many people believe that the scene on the moon wasn't real. Rumours spread throughout coffee shops, street comers, and newspapers, but it soon died down.

    But theories resurfaced in 2001 Suspicion began when an American television network aired a program called Conspiracy Theory: Did We Land on the Moon? The show argued that NASA did not have the money for such a voyage, and that the whole scene was probably filmed in a movie studio. Many critics say that there were no stars in the background during the lunar landing, so it must have been a fake. They also point out that the American flag that was posted was waving. How could that be if there is no wind on the moon?

    NASA(National Aeronautics and Space Administration)has denied these rumours many times. They explained that now photographers can capture the brightness of the astronauts with the dimness of the stars behind them. Also, they said that the flag was waving because the astronauts were pulling it back and forth trying to get it deeper into the rock. NASA also points out that the television program fails to mention that Armstrong and his team brought back 800 pounds of rock from the moon.

    Nell Armstrong is seen as a national icon in the US and his lunar landing is one of the most historic events in the country's history. But either way, this conspiracy theory still exists today.