下列是几个利用放射性同位素示踪的实验，有关叙述不正确的是（）

题干

A：用含¹⁵N标记尿嘧啶的培养液培养植物，一段时间后，根尖分生区细胞中含放射性物质的细胞器有线粒体与核糖体

B：小白鼠吸入¹⁸O₂后呼出的二氧化碳不会含有¹⁸O，但尿液中可以检测到放射性

C：要得到含³²P的噬菌体，必须先用含³²P的普通培养基培养细菌，若用³⁵S标记了噬菌体蛋白质外壳，离心后存在于上清液中

D：给某植物提供¹⁴CO₂和光照等条件，一段时间后可在C₅化合物和蛋白质中发现放射性

上一题下一题 0.0难度选择题更新时间:2012-02-24 04:49:11

B

____Xiao Feng，a student is from China. But she is crazy about American music. And she is only free on Saturday.

____Windy, a Beijing University student comes from England. She wants to know what happened in China in the past.

____Fan Fan is a 13—year—old boy. Tomorrow is his mother's birthday, but he isn't sure what he should buy for her.

____Dan Dan, a 16 —years—old student comes from a poor family. She goes to school from Monday to Friday. And she is looking for a part—time job.

____Xia Mei is a dance lover. She can give a wonderful Chinese dance, but she wants to learn more.

A Live Music—Late Night Jazz

Enjoy real American jazz from Herbie Davis, the famous trumpet player. He is known to play well into the early hours, so don't lose the chance(机会).

B Scottish Dancing

Scottish dancing is nice and easy to learn. The wonderful dance from England will by given.

C Show—Anhaul Museum

There are 12000 pieces on show here .You can see the whole of Chinese history.

D Rose Hotel

1Oct—31Mar. $198 for a night; 1Apr.—30Apr. closed; 1May—30Sep.$218 for a night.

E Wanted

The best gift for the woman who has birthday.

F Saturday Job

Cleaner(16+) for company in Hoe. 8am—1pm only $5 an hour. Tel:47885445

G Reporter Wanted

New Evening Paper is looking for a reporter between 13 and 16 to work from 4pm to 6pm weekday. Tel: 0451—865541

H Prince of the Piano

Richard Clayderman, the French pianist who is widely known as “ the Prince of the Piano”, will give his concert this Sunday night, at 8.00 at Flower

Hall, City College.