14.Every electronic gadget (小玩意) needs good memory.A music player stores songs,albums and playlists.A computer holds schoolwork and programs and remembers how far a player has advanced in his or her favorite game.Mobile phones store names,numbers and hundreds of texts.
Now,scientists in California say they have come up with a way to turn a living cell into a memory device.
It can store only one tiny bit of information,but it's a start.In the future,a cell-based gadget might travel through the body and record measurements.The benefit to human health could be big:the right tool,for example,might record the earliest signs of disease.
Doctors,scientists and other curious people want to know what is happening inside the body,even at levels that can't be seen by the naked eye.So far,there is no device small enough to travel through the bloodstream.
If normal machines won't do the trick,perhaps biology will.Scientists who work in the field of synthetic (合成的) biology are trying to find ways to turn living things into human tools.In the case of the new memory device,bioengineers from Stanford University used the genetic material inside living cells to record information.
This genetic material consists of DNA.Found in nearly every cell,DNA carries all of the information that keeps a living thing alive.
In the new experiment,the researchers turned DNA from bacteria(細(xì)菌) into a switch.They"flip (翻轉(zhuǎn))"a small section of DNA.Then,using the same procedure (過程),the scientists flip the section again-returning it into its normal structure.
Using these DNA switches,"We can write and erase DNA in a living cell,"bioengineer,Jerome Bonnet,explained to Science News.
It might take years before his team or others identity whether a DNA-based memory device might be practical.Right now,it takes one hour to complete a flip.That is far too long to be useful.Plus,a flipped section has a very small little memory-less than what a computer uses to remember a single letter.
"This was an important proof that it was doable,"Bonnet told Science News."Now we want to build a more complex system,something that other people can use."
67.What is the aim of listing the electronic things in the first paragraph?D
A.To make the passage more fashionable.
B.To show how electronic things have memory.
C.To discuss things in detail.
D.To make the subject of the text more understandable.
68.What is possible future benefit of the cell-based gadget for people?A A.To detect disease at the earliest point.
B.To help improve the memory.
C.To help people build a body.
D.To replace many electronic gadgets.
69.What is the object being researched?B
A.The cells of bacteria.
B.The DNA of bacteria.
C.A section of bacteria.
D.The nucleus of bacteria.
70.What do we know about a flipped section of DNA?A
A.It has a very small memory.
B.It can function as a computer.
C.It has one letter in it.
D.It takes a day to complete it.
分析 本文屬于科教類的短文閱讀.主要介紹了科學(xué)家已經(jīng)成功把活細(xì)胞植入了記憶裝置以及現(xiàn)在科學(xué)家正在研究細(xì)菌的DNA.
解答 DABA
67:D.推斷判斷題.第一自然段列舉電子事物的目的是使得這篇文章的主題更容易理解,故選D.
68:A.細(xì)節(jié)理解題.根據(jù)It can store only one tiny bit of information,but it's a start.In the future,a cell-based gadget might travel through the body and record measurements.The benefit to human health could be big:the right tool,for example,might record the earliest signs of disease.可知它的好處在于可以早期發(fā)現(xiàn)疾病,故選A.
69:B.細(xì)節(jié)理解題.根據(jù)In the new experiment,the researchers turned DNA from bacteria(細(xì)菌) into a switch.They"flip (翻轉(zhuǎn))"a small section of DNA.Then,using the same procedure (過程),the scientists flip the section again-returning it into its normal structure.可知正在被研究的物體是細(xì)菌的DNA,故選B.
70:A.細(xì)節(jié)理解題.根據(jù)最后一段That is far too long to be useful.Plus,a flipped section has a very small little memory-less than what a computer uses to remember a single letter.可知,它的記憶存儲(chǔ)量是非常小的,還不及電腦記憶一個(gè)字母的量大;故選A.
點(diǎn)評 解答細(xì)節(jié)理解題時(shí),一個(gè)常用的方法就是運(yùn)用定位法,即根據(jù)題干和選項(xiàng)中的關(guān)鍵詞從原文中找到相關(guān)的句子,與選項(xiàng)進(jìn)行比較從而確定答案;推理判斷題既要求學(xué)生透過文章表面文字信息推測文章隱含意思,又要求學(xué)生對作者的態(tài)度、意圖及文章細(xì)節(jié)的發(fā)展作正確的推理判斷,力求從作者的角度去考慮,不要固守自己的看法或觀點(diǎn).