题目

阅读短文，并按要求完成1～5题。If someone asked you to draw a picture of a robot，how would it look? Like a person? That's how we often picture robots in our minds. But real robots look many different ways.Some robots have TV cameras for eyes. Some have special parts that help them touch. Many have computer brains. How robots look depends on the job they have to do. Some can even have their parts changed，so they can do different jobs.Some robots look like huge insects. America sent some robots to Mars (火星) in 1976. They moved on the surface and did experiments there.Robots 下图中的甲、乙两图为—昼夜中某作物植株对C02的吸收和释放状况的示意图。甲图是在春季的某一晴天，乙图是在盛夏的某一晴天，请据图回答问题： （1）甲图曲线中C点和E点(外界环境中C02浓度变化为零)处，植株处于何种生理活动状态？____________。 （2）根据甲图推测该植物接受光照的时间是曲线中的    段，其中光合作用强度最高的 是     点，植株积累有机物最多的是      点。 （3）乙图中FG段C02吸收量逐渐减少是因为      ，以致光反应产生的      和      逐渐减少，从而影响了暗反应强度，使化合物数量减少，影响了C02固定。 （4）乙图曲线中间E处光合作用强度暂时降低，可能是因为