第34题: [单项选择]How did the government raise money in the past A. By selling services that make life comfortable. B. By selling land containing oil. C. By selling public lands. D. By selling coal and other natural products. 参考答案:C
第35题: [单项选择]下列对门控离子通道型受体的描述哪项有错: A. 它们存在于快速反应细胞的膜上 B. 可称离子通道型受体 C. 由4~5个亚单位穿透细胞膜组成 D. 其亚单位由单一肽链往返4次穿透细胞膜形成 E. 受体激动时离子通道开放仅引起兴奋效应 参考答案:E