试题与答案

已知玉米的黄粒(D)对紫粒(d)为显性,抗病(R)对不抗病(r)为显性,控制上述两对

题型:问答题

题目:

已知玉米的黄粒(D)对紫粒(d)为显性,抗病(R)对不抗病(r)为显性,控制上述两对相对性状的基因分别位于两对同源染色体上。用个体DdRr的花药进行离体培养,在获得由花粉发育成的单倍体植株的同时,也会得到一些由花药壁细胞发育成的二倍体植株。

某研究小组获得的自交及测交结果如下表:

对以上结果,甲、乙两同学作出了自己的判断:

甲同学认为是基因重组的结果,乙同学认为玉米在种植过程中发生了染色体畸变,从而使数据偏离正常值。

你认为哪位同学的判断正确,并请说明你认为这位同学判断正确的理由,再简述你探究该同学的判断正确与否的实验设计思路。

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答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

One evening in February 2007, a student named Paula Ceely brought her car to a stop on a remote road in Wales. She got out to open a metal gate that blocked her path. That's when she heard the whistle sounded by the driver of a train. Her Renault Clio was parked across a railway line. Seconds later, she watched the train drag her car almost a kilometre down the railway tracks.

Ceely's near miss made the news because she blamed it on her GPS (导航仪). She had never driven the route before. It was dark and raining heavily. Ceely was relying on her GPS, but it made no mention of the crossing. "I put my complete trust in the device and it led me right into the path of a speeding train." she told the BBC.

Who is to blame here? Rick Stevenson, who tells Ceely's story in his book When Machines Fail Us, points the finger at the limitations of technology. We put our faith in digital devices, he says, but our digital helpers are too often not up to the job. They are filled with small problems. And it's not just GPS devices: Stevenson takes us on a tour of digital disasters involving everything from mobile phones to wireless keyboards.

The problem with his argument in the book is that it's not clear why he only focuses on digital technology, while there may be a number of other possible causes. A map-maker might have left the crossing off a paper map. Maybe we should blame Ceely for not paying attention. Perhaps the railway authorities are at fault for poor signalling system. Or maybe someone has studied the relative dangers and worked out that there really is something specific wrong with the GPS equipment. But Stevenson doesn't say.

It's a problem that runs through the book. In a section on cars, Stevenson gives an account of the advanced techniques that criminals use to defeat computer-based locking systems for cars. He offers two independent sets of figures on car theft; both show a small rise in some parts of the country. He says that once again not all new locks have proved reliable. Perhaps, but maybe it's also due to the shortage of policemen on the streets. Or changing social circumstances. Or some combination of these factors.

The game between humans and their smart devices is amusing and complex. It is shaped by economics and psychology and the cultures we live in. Somewhere in the mix of those forces there may be a way for a wiser use of technology.

If there is such a way, it should involve more than just an awareness of the shortcomings of our machines. After all, we have lived with them for thousands of years. They have probably been fooling us for just as long.

小题1:What did Paula Ceely think was the cause of her accident?

A.She was not familiar with the road.

B.It was dark and raining heavily then.

C.The railway workers failed to give the signal.

D.Her GPS device didn't tell her about the crossing.小题2: The phrase "near miss" (Paragraph 2) can best be replaced by ________.

A.close hit

B.heavy loss

C.narrow escape

D.big mistake小题3:Which of the following would Rick Stevenson most probably agree with?

A.Modern technology is what we can't live without.

B.Digital technology often falls short of our expectation.

C.Digital devices are more reliable than they used to be.

D.GPS error is not the only cause for Ceely's accident.小题4:In the writer's opinion, Stevenson's argument is ________.

A.one-sided

B.reasonable

C.puzzling

D.well-based小题5:What is the real concern of the writer of this article?

A.The major causes of traffic accidents and car thefts.

B.The relationship between human and technology.

C.The shortcomings of digital devices we use.

D.The human unawareness of technical problems.

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