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问题 单项选择题 B型题

需要载体参与，且需消耗能量的转运机制是（）

A.主动转运

B.被动扩散

C.促进扩散

D.吞噬作用

E.胞饮作用请选择与下列题干相对应的转运机制

答案

参考答案：A

解析：被动扩散不需要载体，膜对药物无特殊选择性，不消耗能量；主动转运需要载体参与，需要消耗机体能量；促进扩散需要载体参与，但不消耗能量；吞噬作用和胞饮作用不需要载体参与，但需要消耗机体能量。

问答题

Alexander has been the general director of -ZAO- JKL for three months. He has a fi xed term contract with the company that expires in 21 months time. On his appointment he was considered to have all the necessary skills to make the company more competitive. As Alexander owns 12% of the shares in the company, he was also regarded as a person who would be highly committed to the future of -ZAO- JKL.The internal auditor recently informed the board of directors of some disturbing facts. In the course of their duties they discovered that Alexander had records of ongoing discussions with key executives of -ZAO- PQR, the company’s main competitor. These records included notes that contained sensitive information on the sales performance and marketing plans of -ZAO- JKL, and it was quite clear that these had been discussed with the executives of the competitor.When the board of directors asked Alexander for an explanation of his actions, he replied that his actions were totally appropriate as it was common business practice to interact with other infl uential people in the industry and that there would be benefi ts for both companies.The board of directors was not satisfi ed with Alexander’s explanation and decided that they would need to consider Alexander’s future position in the company, as well as any action that might be taken to remedy any losses infl icted on the company by his actions.Required:

(b) Discuss the actions that Alexander may take to defend his position. (4 marks)
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多项选择题

曲线附加阻力值大小与下列因素有关（）。

A.曲线半径

B.列车运行速度

C.外轨超高

D.轨距加宽量

E.机车车辆的固定轴距
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