题干

人体患天花时,体内会产生一种抵抗天花病毒的蛋白质,病愈后,这种蛋白质终身存留在人体内,使这个人不再患天花。
(1)在上述过程中,属于抗原的是____ ,病毒进入人体后,淋巴细胞产生抵抗该病毒的____ 。
(2)患过天花的人不会再患天花了,这是因为:病原体被消灭后,有些相应的____ 仍然留存在人体内,当同样的病原体再次侵入时,留存在人体内的相应____ 会迅速消灭它们。
(3)特定的抗体只能消灭特定的____ 。上述免疫过程属于____ 免疫。

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答案(点此获取答案解析)

天花病毒,抗体,抗体,抗体,抗原,特异性免疫

同类题1

阅读下面材料,从每题所给的A、B、C、D四个选项中选出最佳选项。

C

    Mrs. Tan was feeling nervous because her son Tom's exam was coming. This was his national exam and they did not know what to expect. Tom's weakest subject was Chinese. So Mrs Tan had found a private teacher to give him extra lessons to improve his Chinese. Tom, on the other hand, was not showing any interest in the subject. He thought that the extra lessons would not be helpful to his grades at all. So he didn't put much effort into the lesson.

    One day after Tom's Chinese lesson, his teacher spoke to Mrs. Tan. She said that Tom was showing a callous attitude (冷漠的态度) to his work. She was worried about that he might not pass his Chinese exam if he continued being like this. She had no idea that the situation was becoming so terrible. She told the teacher that she would have a word with Tom about it.

    That evening, both Mr. and Mrs. Tan sat down with Tom and talked to him. They wanted to know why his attitude was so bad. They managed not to scold him but instead, talked to him kindly. At first, Tom said nothing. Then, he slowly told them he did not understand his lessons. He said that the teacher's pace (速度) of lesson was too fast for him. Mrs. Tan then advised him to speak up if it happened the next time so that his teacher could slow down. In addition, Mrs. Tan would let his teacher know that she needed to slow down her lessons a little.

    After that heart-to-heart discussion with Tom, the situation improved. His teacher taught him at a pace that was comfortable to him and he in turn, would speak up and ask questions whenever he had problems.

    By the time Tom sat for his exam, he was feeling more confident. When his results came out, he was excited as he had improved a lot in Chinese. Both his parents as well as his private teacher were very proud of him. It goes to show that with an effort, all things are possible.