According to the story, her mother______.
A. thought five pence wasn't much.
B. sent a postal for five pence and an envelop with a stamp and her address
C. asked her to find out the secret quickly.
D. didn't believe the advertisement and didn't want her to do so.
转运内吞是一种特殊的内吞作用，受体和配体在内吞过程中并未作任何处理，只是从一个部位转运到另一个部位。
A. 正确
B. 错误
The passage says that people can faint if they are______.
A. frightened
B. worried
C. happy
D. Both A and B
质膜对Na+的通透性大于K+是静息电位产生的主要原因。
A. 正确
B. 错误
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