本题目来源于试卷: Interaction & Interdependence C.6 Integration of Body Systems，类别为 IB生物学
[单选题]
Which statement correctly describes8f zcs89 7es qvx0slb+ the role of auxin in phototropie3lg +2 flk,;ij.gf m-zcn4oo 6bqvn4sm?
A. High concentrations stimulate cell elongation in the stem.
B. Low concentrations stimulate cell elongation in the stem.
C. High concentrations inhibit cell division in the stem.
D. High concentrations inhibit cell division in the stem.
参考答案: A
本题详细解析:
Explanation: Choice A is correct because high auxin concentrations stimulate cell elongation in the stem tip. Choice B is incorrect because low auxin concentrations do not stimulate cell elongation in the stem tip. Choice C and Choice D are incorrect because in phototropism auxin does not inhibit cell division, it affects cell elongation.
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