DNA (deoxyribonucleic acid) helps to make you who you are. It is like a tiny instruction manual in each of your cells. DNA tells them how they should assemble your body. Your DNA determines what you will look like, and it even has a strong influence on your personality. DNA is very similar from one human to another. In fact, scientists believe that the DNA of all humans is around 99 percent identical. It's that one percent difference that makes us unique individuals. And if that wasn't crazy enough, some studies claim that humans and chimpanzees have DNA that is 96 percent identical. Thus, a difference of one percent can make you bald, but four percent can have you swinging from the trees! A DNA strand is called a "helix," and it looks like a pair of coiled strings. Each helix contains information in the form of chemicals. These chemicals are complicated instructions for the cells in your body. Since the instructions are very complicated, there can sometimes be mistakes when the DNA helix copies itself. This is called a "mutation." Mutations are slight changes in someone's DNA, and these changes can be responsible for serious diseases and other problems. Cancer is one such example. DNA mutations can dramatically increase a person's chance of developing cancer later in life. Scientists have only recently been able to map out the entire DNA helix. This has helped them discover new ways to repair problems in people's DNA. However some people believe that continued DNA research could create negative consequences, like human cloning. Therefore, we should always keep this in mind and be cautious in our future DNA research. DNA(去氧核糖核酸)形塑出你的性格樣貌,它就像是深藏在細胞內的微小操作指南一樣。DNA 會告訴細胞要如何打造你的軀體,你的DNA決定了你的樣貌,甚至影響了你的性格。 每個人類個體的DNA 都十分相似。事實上,科學家認為所有人類的DNA 約99% 雷同。而那1%的細微差異,就足以讓你成為一個獨特的個體。更驚人的是,有些研究宣稱人類和黑猩猩的DNA有96% 相同。也就是說,1% 造成你禿頭與否,而4% 的差異則會影響你是否能在樹間擺盪! DNA 鏈看起來就像兩股纏繞的繩子,稱為「雙螺旋」結構。每條DNA 螺旋上布滿資訊,以化學成分的型態顯示。這些化學成分是給身體細胞的複雜指令。由於這些化學元素太過精密複雜,當DNA 在自我複製時,它們可能會出現問題,這時「突變」就產生了。突變是DNA 的變異,這些變異有時會造成嚴重的疾病和其他問題。癌症即為一例,DNA 突變會大幅增加晚年罹癌的機率。 近來,科學家已經能夠排列出整個DNA序列。DNA 排序的目的是為了修復人類DNA 中的問題。然而有些人認為,持續研究DNA 可能會帶來負面影響,如複製人的問題。在未來的DNA 研究裡,我們應該更加小心謹慎。 |
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