英语六级选词填空

Directions: In this section, there is apassage with ten blanks. You are required to select one word for each blankfrom a list of choices given in a word bank following the passage. Read thepassage through carefully before making your choices. Each choice in the bankis ident ified by a letter. Please mark the corresponding letter for each item on Answer Sheet 2 with a single line through the centre. You may not use any ofthe words in the bank more than once.

A novel way of making computer memories, using bacteria FOR half a century, the (1) __________of progress in the computer industry ha s been to do more with less.

Moore's law famously observes that the number of transistors which ca n be crammed into a given space (2)__________ every 18 months.文档来自于网络搜索

The amount of data that can be stored has grown at a similar rate.文档来自于网络搜索

Yet as (3)__________ get smaller, making them gets harder and mor e expensive.文档来自于网络搜索

On May 10th Paul Otellini, the boss of Intel, a big American chip maker, put the price of a new chip factory at around $10 billion.文档来自于网络搜索

Happily for those that lack Intel's resources, there may be a che aper option—namely to mimic Mother Nature,文档来自于网络搜索

who has been building tiny (4)__________, in the form of living c ells and their components, for billions of years, and has thus got ra ther good at it.文档来自于网络搜索

A paper published in Small, a nanotechnology journal , sets out t he latest example of the (5)__________.文档来自于网络搜索

In it, a group of researchers led by Sarah Staniland at the Unive rsity of Leeds, in Britain, describe using naturally occurring protei ns to make arrays of tiny magnets,文档来自于网络搜索

similar to those employed to store information in disk drives.文档来自于网络搜索

The researchers took their (6)__________ from Magnetospirillum ma gneticum, a bacterium that is sensitive to the Earth's magnetic field thanks to the presence within its cells of flecks of magnetite, a fo rm of iron oxide.文档来自于网络搜索

Previous work has isolated the protein that makes these miniature compasses. Using genetic engineering, the team managed to persuade a different bacterium—Escherichia coli, a ubiquitous critter that is a workhorse of biotechnology—to (7)__________ this protein in bulk.文档来自于网络搜索

Next, they imprinted a block of gold with a microscopic chessboar d pattern of chemicals.文档来自于网络搜索

Half the squares contained anchoring points for the protein.文档来

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The other half were left untreated as controls.

They then dipped the gold into a solution containing the protein, allowing it to bind to the treated squares, and dunked the whole lot into a heated (8)__________ of iron salts.文档来自于网络搜索

After that, they examined the results with an electron microscope.文档来自于网络搜索

Sure enough, groups of magnetite grains had materialised on the t reated squares, shepherded into place by the bacterial protein.文档来自于网络搜索

In principle, each of these magnetic domains could store the one or the zero of a bit of information, according to how it was polarise d.文档来自于网络搜索

Getting from there to a real computer memory would be a long road.文档来自于网络搜索

For a start, the grains of magnetite are not strong enough magnet s to make a useful memory, and the size of each domain is huge by mod ern computing (9)__________.文档来自于网络搜索

But Dr Staniland reckons that, with enough tweaking, both of thes e objections could be dealt with.文档来自于网络搜索