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  It was very hot in the middle of summer and there were no trees 1the street. Mr. Read 2 his shop at half past five, and went 3 into the street and began walking to the bus stop. He was very 4. The sun shone straight down the street, and in a few minutes Mr. Read5very hot.

     A small boycame out of another6 in the street and 7Mr. Read. He stayed very8 him all the time, and he kicked Mr. Read's 9several times. Mr. Read looked at him 10 each time.

     After thefourth time, Mr. Read stopped, turned 11 and said to the small boy, "What are you doing? 12 following me like that! You're going to 13 my feet."

     "I'm 14, but don't stop me, please!" The small boy said, "It's very hot today, and there isn't 15shade anywhere else in the street."

为研究乙烯影响植物根生长的机理，研究者以拟南芥幼苗为材料进行试验．

（1）乙烯和生长素都有通过与____ 结合，将____ 传递给靶细胞，从而调节植物的生命活动．

（2）试验：将拟南芥幼苗分别放在含有不同浓度ACC的培养液中培养，12小时后测定幼苗根生长素的含量，试验结果如图所示，据图分析，乙烯通过促进____ 来影响根生长．

（3）研究者将拟南芥幼苗放在喊NPA（生长素极性运输阻断剂）的培养液中培养，一段时间后，比较试验组和对照组幼苗根伸长区细胞长度，结果无显著差异，由此分析，研究者的目的是探究乙烯是否通过影响____来影响根生长．

（4）综合上述各实验的结果可推测，乙烯对根生长的作用最可能是通过促进生长素的____ 实现的．

林区保护员小郭被诊断为夜盲症．为辅助治疗，他平时应多吃（    ）