问题
单项选择题
关于病毒癌基因论述准确的是
A．主要存在于沅病毒中
B．在体外不能引起细胞转化
C．感染宿主细胞能随机整合于宿主细胞基因组
D．又称为原癌基因
E．可直接合成蛋白质
答案
参考答案：C
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关于病毒癌基因论述准确的是
A．主要存在于沅病毒中
B．在体外不能引起细胞转化
C．感染宿主细胞能随机整合于宿主细胞基因组
D．又称为原癌基因
E．可直接合成蛋白质
参考答案：C
| 完形填空 I live in a big city with a lot of homeless people. Luckily there're small ways of helping them and you needn't have a lot of__1__. One way to help is to buy their monthly magazine.__2__doing this one day, I got to __3__a young homeless man. He was often__4__the magazine at the train station. He was a poor farmer from another country. After a while, I discovered that his__5__was close to mine. It__6__that we were born in the same month. I met him last year__7__after his birthday, and after congratulating(祝贺) him, without__8__, I asked if he had had a good day. He__9__and said that he hadn't really celebrated. I felt so __10__. I just couldn't bear the thought of (不敢想)this nice, young man being__11__on his 25th birthday with no presents, no cake, nothing! So I went home and looked in my yarn(纱线) basket.__12__for me, I had enough yarn__13__. I set to work and knitted(编织) a__14__for the young man. The yarn had become a little dirty__15__I didn't knit very often. Then I washed the yarn so the scarf would be__16__when he got it. I met him on my own birthday as I was going shopping. I had__17__to meet him so I had__18__the scarf and a piece of my own birthday__19__around with me. He was very happy with these gifts and so was I. The__20__in his eyes was the best present he could have given me! | ||||
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