移植到人体的器官不宜成活，从免疫的功能来分析，这属于
A．清除细胞
B．过敏反应
C．抵抗抗原的侵入
D．对疫苗的正常反应
答案：C
题目分析：免疫是指人体的一种生理功能，人体依靠这种功能识别自己和非己成分，从而破坏和排斥进入体内的抗原物质，或人体本身产生的损伤细胞和肿瘤细胞等，以维持人体内部环境的平衡和稳定，免疫的三大功能包括防御、自我稳定、免疫监视，移入的器官对于病人来说是非己的成分，相当于抗原，人体依靠免疫功能能对进入其体内的外来的“非己”组织器官加以阻挡和清除，导致移植器官破坏和移植失败，这种生理免疫过程在临床上表现为排斥反应。
点评：此题为基础题，稍有一定的难度，解答此题的关键是掌握免疫的概念和免疫的三大功能：防御、自我稳定、免疫监视。
A new term has begun. Teachers are __36__ about the fact that new students are not easy to handle. They like to bring cellphones and MP3 players to school. What is __37__, some students even use cellphones to do with out-of-class matters in class, or sometimes just for fun. Some other students listen to MP3 players when they are having a lesson that they are not interested in. Are these new students really that __38__? ‘Yes,’ says Delaney Kirk, a professor at Drake University. __39__ she adds it’s not their fault. Instead, the things that they bring into school --- cellphones, MP3 players and so on --- and the teachers are to blame. Kirk first began thinking about students’ manners six years ago. ‘I had my first class in which students were sleeping or talking to each other. It seemed that learning well __40__ nothing to do with them,’ she says. ‘At first, I got worried about this, but then I said to myself, “You’re teaching __41__, and you need to manage this … These students need to know more about manners. It’s time to help them develop some good __42__. They shouldn’t waste time doing nothing when they are young. Sooner or later, they might regret the time they have wasted.”’ Kirk also __43__ a list of suggestions to help teachers better manage their classes. The following are among her suggestions: Tell students how they will benefit by taking the class. On the first day of class, emphasize its importance __44__ giving some homework that students must turn in next time. Do not allow them to bring cellphones and MP3 players to the class at all. Decide __45__ formal and informal the class will be.
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