万物简史 第575期:生命的物质(1)
26 The Stuff of Life 第二十六章 生命的物质 If your two parents hadn't bonded just when they did possibly to the second, possibly to the nanosecond you wouldn't be here. And if their parents hadn't bonded in a precisely timely manner, you wo
万物简史 第576期:生命的物质(2)
If you go back sixty-four generations, to the time of the Romans, the number of people on whose cooperative efforts your eventual existence depends has risen to approximately 1,000,000,000,000,000,000, which is several thousand times the total number
万物简史 第577期:生命的物质(3)
The tiny differences in that remaining 0.1 percent roughly one nucleotide base in every thousand, to quote the British geneticist and recent Nobel laureate John Sulston are what endow us with our individuality. Much has been made in recent years of t
万物简史 第578期:生命的物质(4)
DNA exists for just one reason to create more DNA and you have a lot of it inside you: about six feet of it squeezed into almost every cell. Each length of DNA comprises some 3.2 billion letters of coding, enough to provide 103,480,000,000 possible c
万物简史 第579期:生命的物质(5)
That is why it can be recovered from patches of long-dried blood or semen in murder investigations and coaxed from the bones of ancient Neandertals. It also explains why it took scientists so long to work out how a substance so mystifyingly low key s
万物简史 第580期:生命的物质(6)
DNA didn't do anything at all, as far as anyone could tell. It just sat there in the nucleus, possibly binding the chromosome in some way or adding a splash of acidity on command or fulfilling some other trivial task that no one had yet thought of. T
万物简史 第581期:生命的物质(7)
Working with a kind of chemical clerk called a ribosome, RNA translates information from a cell's DNA into terms proteins can understand and act upon. 在一种核糖体的化学物质的帮助下，RNA将细胞里的DNA信息以蛋白质所能理解的
万物简史 第582期:生命的物质(8)
As laboratory specimens fruit flies had certain very attractive advantages: they cost almost nothing to house and feed, could be bred by the millions in milk bottles, went from egg to productive parenthood in ten days or less, and had just four chrom
万物简史 第583期:生命的物质(9)
The problem, however, remained the next level of biological intricacy: the enigmatic genes and the DNA that composed them. These were much trickier to isolate and understand. As late as 1933, when Morgan was awarded a Nobel Prize for his work, many r
万物简史 第584期:生命的物质(10)
Finally, in 1944, after fifteen years of effort, a team at the Rockefeller Institute in Manhattan, led by a brilliant but diffident Canadian named Oswald Avery, succeeded with an exceedingly tricky experiment in which an innocuous strain of bacteria
万物简史 第585期:生命的物质(11)
In an exceedingly distinguished career, he would win two Nobel Prizes (for chemistry in 1954 and peace in 1962), but with DNA he became convinced that the structure was a triple helix, not a double one, and never quite got on the right track. Instead
万物简史 第586期:生命的物质(12)
Crick, twelve years older and still without a doctorate, was less memorably hirsute and slightly more tweedy. In Watson's account he is presented as blustery, nosy, cheerfully argumentative, impatient with anyone slow to share a notion, and constantl
万物简史 第587期:生命的物质(13)
The New Zealand-born Wilkins was a retiring figure, almost to the point of invisibility. A 1998 PBS documentary on the discovery of the structure of DNA a feat for which he shared the 1962 Nobel Prize with Crick and Watson managed to overlook him ent
万物简史 第588期:生命的物质(14)
If Franklin was not warmly forthcoming with her findings, she cannot be altogether blamed. Female academics at King's in the 1950s were treated with a formalized disdain that dazzles modern sensibilities (actually any sensibilities). However senior o
万物简史 第589期:生命的物质(15)
To Wilkins's presumed dismay and embarrassment, in the summer of 1952 she posted a mock notice around the King's physics department that said: It is with great regret that we have to announce the death, on Friday 18th July 1952 of D.N.A. helix... . I
