Many people think that information technology and biotechnology will rule the 21st century. Robert Birge, a chemist at the University of Connecticut, is trying to combine them, by making computer memories out of protein.
The protein in question is bacteriorhodopsin (bR), a molecule that undergoes a structural change when it absorbs light. By using genetic engineering to tweak wild bR from a bacterium called Halobacterium salinarum, Dr Birge and his colleagues have made a variety of the molecule that they claim is well-suited to act as an element of a computer's memory. Hit with a green light, it adopts one shape. Hit subsequently with a red light, it twists itself into another. Then, if hit with blue light, it resets itself into its original state.
To make a memory from the protein, Dr Birge suspends elements made from it in a transparent plastic cube known as a cuvette. A pair of lasers arranged at right angles to one another write data into the cuvette by shining in turn on "slices" through the plastic matrix. The first laser, which produces green light, sweeps the whole cuvette, causing its protein contents to take on a shape that (in binary code) is designated as "zero". The second laser, which produces red light, then stimulates particular sites to take the second shape. This corresponds to "one" in binary code. Once the lasers are switched off, data recorded this way will, according to Dr Birge, remain stable for more than 12 years.
To read the stored data, a low-powered red laser is shone slice by slice through the cuvette. This does not disturb the conformation of the protein molecules; but those in state "zero" absorb light at this wavelength. A machine placed behind the cuvette detects this absorption pattern and translates it into the appropriate string of ones and zeroes. Once the contents have been read into a more conventional storage device, the cuvette can be wiped clean and reset by illuminating it with a blue laser.
Dr Birge says that each cuvette can now hold about seven gigabytes of data (a small laptop computer might have about this much space on its hard drive). He hopes to boost that figure to ten gigabytes by finding a better-performing variety of the protein. Only those with deep pockets, however, could afford the $25,000 cost of each device.
Luckily for Dr Birge, the deep-pocketed American air force thinks that bR cuvettes could be a good way to equip its aircraft and satellites with light, high-density devices to store the mountains of images collected during reconnaissance missions. A protein-based memory is particularly suitable for this, because the bR molecule is robust enough to withstand the barrage of radiation from space that wreaks havoc on conventional magnetic-memory devices operating at high altitude.
1. What is the passage mainly about?
[A]What will rule the 21st century.
[B]How bacterial protein can be used in computers.
[C]What we can get from bacterial protein.
[D]How to make bacterial protein.
2. The application of bR turns out to be___________.
[A]very trustworthy
[B]rather superficial
[C]somewhat contradictory
[D]quite encouraging
3. The basic problem of applying bR to computer lies in ____________.
[A]limited space on hard drive
[B]its complexity
[C]its high price
[D]its limited users
4. Which of the following is not the advantage of bR?
[A]Working at higher altitude.
[B]Light weight.
[C]High density.
[D]Safe from strong radiation.
5. Which of the following is true according to the text?
[A]bR has a wide variety of application in life.
[B]The protein molecules have stable characteristics.
[C]The data recorded with bR can be kept for a long time.
[D]The new device will replace conventional storage device.
答案：BDCAC
篇章剖析
本文论述了信息技术和生物工程学如何完美地结合在用蛋白质做电脑存储器这一新技术当中。第一段引出论点；第二段、三段和四段详细介绍这一技术的具体实施；第五段和六段介绍这一技术的应用情况。
词汇注释
bacteriorhodopsin[bAk9tIErIErEJ`dCpsIn]n.细菌视紫红质，类似于视紫红质的亲盐杆菌属，出现在细菌细胞膜上的紫色色素，它把阳光直接转变成化学能。
tweak vt. 扭，拧，掐；调节；调整
hit vt. 瞬时干扰；瞬时中断
deep pocket 财富，资产
havoc [5hAvEk] n. 大破坏; 蹂躏; 毁坏; 浩劫; 大混乱
play [raise] havoc with [among] 对...造成严重破坏, 使...陷入大混乱
wreak [ri:k] vt. 泄(怒); 雪(恨)；惩罚, [古]报仇；施加, 造成(祸灾)
难句突破
A pair of lasers arranged at right angles to one another write data into the cuvette by shining in turn on "slices" through the plastic matrix.
主体句式：A pair of lasers …write data …
结构分析：本句是一个简单句。句子的主语是“a pair of lasers”，“arranged at right angles to one another”是后置定语，用来修饰主语；谓语是“write”；“by”做伴随状语，短语“in turn”意思是“轮流”。
句子译文：一对事先调整到一个合适角度的激光器通过塑料矩阵轮流在“切片”上闪烁，这样就把数据写入试管。
题目分析
1．答案为B，属主旨大意题。文章第一段点出了本文的论题。
2. 答案为D，属推理判断题。综观全文，虽然bR用在电脑中，其售价不菲，但是其使用效果，以及在军事领域中的运用都说明这一应用是非常鼓舞人心、令人看好的。
3. 答案为C，属事实细节。原文对应信息是“Only those with deep pockets, however, could afford the $25,000 cost of each device.”这一句话中，关键是要理解“deep pockets”的含义。它的意思是“财富，资产”，暗示了这一产品售价高昂。
4. 答案为A，属事实细节题。原文对应信息是“…because the bR molecule is robust enough to withstand the barrage of radiation from space that wreaks havoc on conventional magnetic-memory devices operating at high altitude.”，我们无从判断bR是否能在更高的高度上正常运转。
5. 答案为C，属事实细节题。原文对应信息是“This corresponds to "one" in binary code. Once the lasers are switched off, data recorded this way will, according to Dr Birge, remain stable for more than 12 years.”。
参考译文
许多人认为，信息技术和生物工程学将主宰21世纪。康涅狄格大学的化学家罗伯特•伯奇正在设法通过用蛋白质做电脑存储器的方法把它们结合在一起。
所说的蛋白质就是细菌视紫红质(bR)，即一种分子，当它吸收了光线以后，就会发生结构变化。伯奇博士和他的同事应用遗传工程从一种叫做嗜盐菌的细菌中提取混乱无序的细菌视紫红质，培养出各种各样的分子。他们声称这些分子非常适合做计算机的存储元件。若用绿光对它进行瞬(时干)扰，它呈现一种形状；若再用红光瞬扰, 它便变成另一种形状；然后再用蓝光瞬扰，它便恢复到其原始状态。
为了用蛋白质做存储器，伯奇博士把用蛋白质研制成的元素悬浮在一个透明塑料试管中。此时，一对事先调整到一个合适角度的激光器通过塑料矩阵轮流在“切片”上闪烁，这样就把数据写入试管。产生绿光的第一个激光器扫描整体试管，导致其中的蛋白质成分呈现一种在二进制编码中被定为“0’的形状。产生红光的第二个激光器刺激某些地方，使其呈现第二种形状，此形状对应于二进制编码中的“1”。据伯奇博士说，一旦这些激光器被断开后，用这种方式记录下来的数据能稳定地保留12 年以上。
读取存储的数据时，就让一个低能红色激光器通过试管一片一片地发光。这不会干扰蛋白质分子的构造，但那些“0”状态的蛋白质分子将吸收这个波长的光。放置在试管后面的机器可检测吸收图形，并把它转换成适当的一列含有“1”和“0”的数字。当其中的内容读入一个更常规的存贮设备后，通过蓝色激光器的闪烁就可使试管清零复位。
伯奇博士说，每支这样的试管现在可保存约七十亿字节的数据(一台小型手提电脑的硬盘也就这么大的空间)。他希望通过找到一种性能更好的蛋白质把这个数字提高到100亿字节。不过，只有那些家财万贯的人才能买得起每台价值25,000美元的计算机。
伯奇博士感到幸运的，财力雄厚的美国空军认为bR试管可能是一种用重量轻、密度高的存储设备装备其飞机和卫星的好方法。这种设备可以用来储存储存侦察飞行中收集到的大量图像。蛋白质存储器特别适合这种用途，因为bR分子十分强壮，足以承受来自太空的大量辐射。这种辐射会对在高空运行的常规磁芯式存储器造成严重破坏。