7. Snyder et al suggest that caffeine’s ability to bind to A1 and A2 receptors can be at least partially attributed to which of the following？
（A） The chemical relationship between caffeine and phosphodiesterase
（B） The structural relationship between caffeine and adenosine
（C） The structural similarity between caffeine and neurotransmitters
（D） The ability of caffeine to stimulate behavior
（E） The natural occurrence of caffeine and adenosine in the brain
8. The author quotes Snyder et al in lines 38-43 most probably in order to
（A） reveal some of the assumptions underlying their theory
（B） summarize a major finding of their experiments
（C） point out that their experiments were limited to the mouse
（D） indicate that their experiments resulted only in general correlations
（E） refute the objections made by supporters of the older theory
9. The last paragraph of the passage performs which of the following functions？
（A） Describes a disconfirming experimental result and reports the explanation given by Snyder et al in an attempt to reconcile this result with their theory.
（B） Specifies the basis for the correlation observed by Snyder et al and presents an explanation in an attempt to make the correlation consistent with the operation of psychoactive drugs other than caffeine.
（C） Elaborates the description of the correlation observed by Snyder et al and suggests an additional explanation in an attempt to make the correlation consistent with the older theory.
（D） Reports inconsistent experimental data and describes the method Snyder et al will use to reanalyze this data.
（E） Provides an example of the hypothesis proposed by Snyder et al and relates this example to caffeine’s properties.
參考答案：DDDA DEBBA
以上GMAT閱讀材料幫助大家備考GMAT，希望大家在考試中取得理想成績，同學(xué)們加油！
（A） The chemical relationship between caffeine and phosphodiesterase
（B） The structural relationship between caffeine and adenosine
（C） The structural similarity between caffeine and neurotransmitters
（D） The ability of caffeine to stimulate behavior
（E） The natural occurrence of caffeine and adenosine in the brain
8. The author quotes Snyder et al in lines 38-43 most probably in order to
（A） reveal some of the assumptions underlying their theory
（B） summarize a major finding of their experiments
（C） point out that their experiments were limited to the mouse
（D） indicate that their experiments resulted only in general correlations
（E） refute the objections made by supporters of the older theory
9. The last paragraph of the passage performs which of the following functions？
（A） Describes a disconfirming experimental result and reports the explanation given by Snyder et al in an attempt to reconcile this result with their theory.
（B） Specifies the basis for the correlation observed by Snyder et al and presents an explanation in an attempt to make the correlation consistent with the operation of psychoactive drugs other than caffeine.
（C） Elaborates the description of the correlation observed by Snyder et al and suggests an additional explanation in an attempt to make the correlation consistent with the older theory.
（D） Reports inconsistent experimental data and describes the method Snyder et al will use to reanalyze this data.
（E） Provides an example of the hypothesis proposed by Snyder et al and relates this example to caffeine’s properties.
參考答案：DDDA DEBBA
以上GMAT閱讀材料幫助大家備考GMAT，希望大家在考試中取得理想成績，同學(xué)們加油！