问题
单项选择题
有关受精，下列说法错误的是：（）
A．受精是精子和卵子结合的过程
B．精子必须获能后才具受精能力
C．精子与卵子相遇时发生顶体反应
D．生理情况下，受精一般发生在排卵后12 h内
E．已获能的精子穿过次级卵母细胞透明带是受精完成的标志
答案
参考答案：E
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有关受精，下列说法错误的是：（）
A．受精是精子和卵子结合的过程
B．精子必须获能后才具受精能力
C．精子与卵子相遇时发生顶体反应
D．生理情况下，受精一般发生在排卵后12 h内
E．已获能的精子穿过次级卵母细胞透明带是受精完成的标志
参考答案：E
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| Most people were asleep at night, but Frank was 1 . Frank was a night watchman. His work was to guard a large factory. He had to keep everything 2 . He felt lonely because there was 3 there to talk with. Frank liked his work. If he heard a noise, he went 4 to see what it was. Most of time he walked around inside the big building but he also walked around outside 5 . When he was 6 , he could sit on a chair by the door. In the winter it was very cold. He 7 a warm coat when he left the factory. Last night when Frank went outside, he heard a noise near the gate of the factory. He went very quietly to the noise to see 8 somebody was there, but he saw only a small dog. It looked cold and sad. He took the dog inside the factory and the happy dog 9 him around. The dog was a good friend for the night watchman. Frank was no longer 10 . He could talk to the dog. | ||||
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