题目

曲线图可用来直观地表示生命体内的生理变化。以下对三幅植物生理活动曲线图（如图）的解释，正确的是（ ） A . 图甲表示大豆种子萌发成幼苗过程中，幼苗细胞鲜重的变化 B . 图乙表示一段时间内某植物叶片吸收二氧化碳与光照强度的关系 C . 图丙表示一天内大棚中CO2含量的变化，在a点打开通风孔的目的是给大棚补充氧气 D . 图丙曲线显示，大棚内的生物在13﹣17时段内呼吸作用强度没有变化April 22 is Earth Day. Everyone on Earth should care about and protect the earth!The earth has warmed by about 1°F (华氏度) over the past 100 years, but why and how? Well, scientists are not quite sure. Maybe the earth gets warmer and warmer on its own. But many scientists say that people are doing many things which make the earth warmer. First, greenhouse effect (温室效应) is a very important reason for the change of the earth. People give out too much energy into the air every year. It makes the earth warmer. Climate (气候) change is another important reason. Sometimes it becomes too hot and sometimes too cold. Sometimes there is too much rain and sometimes too little. The change of the climate makes the earth warmer. In turn, the warmth of the earth changes the climate, too.When the earth becomes warmer, there may be more rain and a rise in sea level. It will affect the growth of plants, animals and people. On a Pacific island, 100 people have to move to higher ground because the sea is rising. These people can no longer live on the coast. Before that, two islands without people went underwater in 1999. Scientists say that the seas can rise by nearly one meter by 2100.People can affect the earth's air, land and water. As for us, we can do many things to protect the earth. For example, we can use fridges less. We can tell more people about protecting the earth.1.Earth Day is probably set for people to ______.A.learn more about the earthB.make full use of the earthC.take better care of the earth.D.study the warmth of the earth2.Greenhouse effect comes from______.A.sea rising B.climate changeC.nature's unbalance D.people's activity3.According to the passage, _______ many affect each other.A. animals and islandB. climate and the warmth of the earthC. fridges and animalsD. sea level and the growth of plants4.We can infer (推断) from the passage that the reasons for the warmer earth are______ now.A.not very clear B.completely secretC.well known D.not given yet5.The passage mainly tells us that ______.A.there is more rain nowB.we should protect the earthC.we must stop pollutionD.sea level is getting higher