问题 选择题

到了冬天,杨树和柳树的叶子纷纷落下,而松树、柏树却依然郁郁葱葱,这表明(  )

A.杨树和柳树不适应寒冷的环境

B.松柏比杨柳更适应寒冷的环境

C.松柏和杨柳进行着生存斗争

D.它们都能适应寒冷的环境

答案

生物必须适应环境才能生存,如沙漠上的植物必须耐旱才能生存,而需水较多的水莲在很难成活.冬天,杨树和柳树的叶子纷纷落下,可以降低蒸腾作用,减少因进行蒸腾作用的热量散失,避免因温度过低而冻伤甚至冻死,因此冬季植物落叶是植物对冬季寒冷环境的一种适应.松树、柏树的叶细如针,叶的气孔较少,而且气孔深陷表皮下,叶的表面还有一层蜡质保护,因此蒸腾作用非常弱,可以减少热量散失,适应冬天寒冷的环境.

故选D.

阅读理解

Climate is the average weather usually taken over a 30-year time period for a particular region and time period. Climate is not the same as weather, but rather, it is the average pattern of weather for a particular region. Weather describes the short-term state of the atmosphere (大气).

The climate is changing. Many agreed that climate change may be one of the greatest threats (威胁) facing the planet. Recent years show increasing temperatures in various regions, and/or increasing extremities (极端性) in weather patterns.

Is the Earth getting warmer? Yes! The Earth has warmed by about 1°F over the past 100 years. But why? Well, scientists are not exactly sure. The Earth could be getting warmer on its own, but many of the world’s leading climate scientists think that things people do are helping to make the Earth warmer.

Global Warming may be a big problem, but can you make a difference? Yes! There are several little things you can do to make a difference. Try carpooling. This will help reduce the amount of fossil fuels going into the atmosphere. Whenever you use electricity, you help put greenhouse gases into the air. Turn off lights, the television, and the computer when you are through with them. Also, planting trees is fun and a great way to reduce greenhouse gases. Trees absorb carbon dioxide, a greenhouse gas, from the air. Finally, don’t forget about recycling.

小题1:Climate is         weather.

A.the same as

B.different from

C.a kind of

D.part of小题2: The Earth has warmed by about 1°F over the past 100 years         .

A.only because of human activities

B.but scientists are not exactly sure of the reasons.

C.and we can do nothing to it.

D.and it’s getting warmer on its own小题3:Global Warming may be a big problem, but we can do the following things to make a difference except          .

A.carpooling

B.saving electricity

C.cutting down more trees

D.recycling小题4:What can be the best title of the article?

A.Climate and weather.

B.Weather and climate changing.

C.Climate changing and global warming.

D.Weather and global warming.

选择题