The author mentions specific effects that auxi
问题详情
The author mentions specific effects that auxin has on plant development in order to illustrate the______
A．point that some of the effects of plant hormones can be harmful
B．way in which hormones are produced by plants
C．hierarchical nature of the functioning of plant hormones
D．differences among the best-known plant hormones
E．concept of pleiotropy as it is exhibited by plant hormones请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：E
解析：ThebestanswerisE.Thesecondparagraphstatesthatthefivemajorplanthormones,includingauxin,arepleiotropicandindicatesthateachpleiotropichormonehas“morethanoneeffectonthegrowthanddevelopmentofplants”(lines15-16).Theeffectsofauxinarethenlistedindetailtoprovideanexampleofthedifferenteffectsapleiotropichormonecanhaveonaplant.Thus,thespecificeffectsofauxinarementionedtoillustratetheconceptofpeiotropyasitisexhibitedbyplanthormones.ChoiceCcanbeeliminatedbecausethespecificeffectsthatauxinhasonplantdevelopmentarenotdiscussedinthecontextofthehierarchyofhormones.ChoiceA,B,andDareincorrectbecausetheycitetopicsthatarenordiscussedinthepassage.
