试题与答案

科学家研究发现紫外线可以抑制植物生长,原因是紫外线增加了植物体内吲哚乙酸氧化酶的

题型:实验题

题目:

科学家研究发现紫外线可以抑制植物生长,原因是紫外线增加了植物体内吲哚乙酸氧化酶的活性,从而促进了生长素氧化为3-亚甲基氧代吲哚,而后者没有促进细胞伸长的作用。现在提供生长状况相同的健康的小麦幼苗若干作为实验材料,请完成下列实验方案,以验证紫外线抑制植物生长与生长素的氧化有关。

(1)步骤1:将小麦幼苗平均分为甲组和乙组。

(2)步骤2:给予甲组___________光照,给予乙组_________光照。

(3)步骤3:观察两组幼苗的__________并测量_____________的含量。

(4)预测实验结果及结论:_____________________________________。

答案:

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