第8题: [多项选择]下列关于化学性突触传递特征的叙述,正确的是 A. 双向传播 B. 不衰减传递 C. 兴奋节律不变 D. 对内环境变化敏感 参考答案:D 答案解析:[解释] 神经纤维传导兴奋具有以下特征:①完整性。②绝缘性。③双向性。④相对不疲劳性。化学性突触传递主要表现为以下几方面的特征。①单向传播。②中枢延搁。③兴奋的总和。④兴奋节律的改变。⑤后发放。⑥对内
第19题: [单项选择]A journal kept by the officer of the watch in which day to day happenings are recorded regarding the deck department is the(). A. cargo record book B. deck rough log C. bell book D. Official Logbook 参考答案:B
第33题: [单项选择]In Beijing they______ a marriage certificate, and held a wedding ceremony the following week in Hong Kong. A. gained B. made C. obtained D. earned 参考答案:C 答案解析:[考点] 动词辨析 gain、obtain 和 earn 都有“获得”之意,gain 指得到想要的或所需的事物、益处;obtain指通过买、借、拿等方式去取得,earn 指通过投资或付出努力、艰辛而