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(细菌) into a switch. They “flip (翻转)” a small section of DNA. Then, using the same procedure (过程) , 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.” 小题1:What is the aim of listing the electronic things in the first paragraph?
A. The cells of bacteria. B. The DNA of bacteria. C. A section of bacteria. C. The nucleus of bacteria. 小题4:What do we know about a flipped section of DNA?
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