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24 Cells
第二十四章 令人驚嘆的細胞
It starts with a single cell. The first cell splits to become two and the two become four and so on. After just forty-seven doublings, you have ten thousand trillion (10,000,000,000,000,000) cells in your body and are ready to spring forth as a human being. Actually, quite a lot of cells are lost in the process of development, so the number you emerge with is really just a guess. Depending on which source you consult the number can vary by several orders of magnitude. The figure of ten thousand trillion (or quadrillion) is from Margulis and Sagan, 1986. And every one of those cells knows exactly what to do to preserve and nurture you from the moment of conception to your last breath.
生命開始于一個細胞。第一個細胞一分為二，二又分為四，以此類推，僅僅到第47次加倍以后，你就有了l億億（10000000000000000）個細胞，并作好了最終形成一個人的準備。事實上，在你的一生中，有許多細胞中途離你而去，因此你身上的細胞數只是一種估計。根據資料來源的不同，這個數字可能相差好幾個數量級。1億億這個數字取自馬古利斯和薩根的《微觀世界》。從卵子受精的那一刻起，一直到你離開人世，為了維持和保護你，這些細胞中的每一個都完全知道自己的職責。
You have no secrets from your cells. They know far more about you than you do. Each one carries a copy of the complete genetic code—the instruction manual for your body—so it knows not only how to do its job but every other job in the body. Never in your life will you have to remind a cell to keep an eye on its adenosine triphosphate levels or to find a place for the extra squirt of folic acid that's just unexpectedly turned up. It will do that for you, and millions more things besides.
對于你的細胞來說，你無任何秘密可言，它們對于你的了解，遠遠超過你對自己的了解。每一個細胞都帶有一整套基因密碼——你身體的指令手冊，因此它不僅知道怎樣做自己的工作，而且對于你體內的其他任何一項工作，它都了如指掌。在你的一生中，你永遠沒有必要提醒任何一個細胞，要它隨時注意其腺嘌呤核苷三磷酸鹽的情況，或是找到存放不期然間出現的多余葉酸的地方。它將會為你做這樣的一些事，以及幾百萬件別的事。
Every cell in nature is a thing of wonder. Even the simplest are far beyond the limits of human ingenuity. To build the most basic yeast cell, for example, you would have to miniaturize about the same number of components as are found in a Boeing 777 jetliner and fit them into a sphere just five microns across; then somehow you would have to persuade that sphere to reproduce.
每個細胞都是自然界的一個奇跡。即便是最簡單的細胞，其構造的精巧程度也是人類的智慧所永遠也無法企及的。舉個例子，即便是制造一個基本的酵母細胞，你所需要的零部件就和一架波音777噴氣式飛機的一樣多，而且還必須在直徑僅有5微米的球體內將它們組裝起來，然后你還得以某種方式驅使那個球體進行繁殖。
