单项选择题 关于兴奋性突触传递的叙述，哪一项是错误的 A. 突触前轴突末梢去极化 B. Ca2+由膜外进入突触前膜内 C. 突触小泡释放递质，并与突触后膜受休结合 D. 突触后膜对Na+、K+、Ca2+，特别是对K+的通透性升高

不定项选择 The Blue Eyes Beads, which are signs of protection against evil spirit, are considered one of the most popular tourist souvenirs in Turkey.

单项选择题 A、正确 B、错误