题目

在探索遗传物质的过程中，赫尔希和蔡斯做了T2噬菌体侵染细菌的实验，其中一组实验如下图所示（用32P标记的噬菌体侵染普通大肠杆菌培养物），下列有关叙述中正确的是A. 该组实验证明了DNA是遗传物质，蛋白质不是遗传物质B. 将普通噬菌体放在含32P的培养液中即可得到32P标记的噬菌体C. 上清液检测到放射性的原因可能是步骤①的时间过长或过短D. 该实验中运用了放射性同位素标记技术和差速离心技术fast, invent, thought, play, to, run, music，from，he，become，it，make  Piano music sounds beautiful. Almost everyone wants to own a piano and 1it in the light of candles. It's romantic(浪漫的).Of course we humans play the piano with our ten fingers. But Teotronica plays the piano with 2 19 fingers.  Teotronica isn't a human. It's a robot. It was 3 by Matteo Suzzi. Matto Suzzi is 4 Italy. When he was a child，he 5 interested in science. He had many wild and crazy 6 and created some new amazing things. It took him four years to make the 7 robot. 8 the robot cost him about $ 4700.Teotronica plays the piano 9 than a human because it has more fingers than humans. Teotronica can also sing along 10 the music that it is playing. It's the first robot to do so. Isn't it amazing?1. 2._______ 3.________ 4. _____ 5.__________ 6.________ 7._______ 8.________ 9.________ 10.