美国科学60秒 SSS 2013-07-30
时间：2018-12-24 作者：英语课 分类：Scientific American(七)月
英语课
This is scientific american 60-secs science. I'm Sophy Bushwick. Got a minute?
It takes a white chromosome 1 to make a man, but that does't mean its counterpart, the x-chromosome, plays no part. In fact it has a big role in making sperm 2.
To study x evolution, experts first sequence human chromosome more accurate than it ever before. Then they compare the code to that of a mammal whose evolutionary 3 lineage spit from ours about 80m yrs before, the mouse. It turns out that human and mice share 95% of their x-genes 4, this finding was no surprise.
In the 1960s, biology S.O. suggests that the x-chromosome would evolve slowly and almost remain similar in most mammalia species. But something did change over evolutionary time, or rather 144 things. 144 human x-chromosome genes had no counterparts in mince 5 and these genes seems to be constantly developing. Many of the genes remained domain 6 in female, only become productive in tissues involved in sperms 7 production. Clearly, the ex-chromosome exceeds its feminine responsibilities, which is excellent news for male fertility.
1 chromosome
n.染色体
- Chromosome material with exhibits of such behaviour is called heterochromatin.表现这种现象的染色体物质叫做异染色质。
- A segment of the chromosome may become lost,resulting in a deletion.染色体的一个片段可能会丢失，结果产生染色体的缺失。
2 sperm
n.精子，精液
- Only one sperm fertilises an egg.只有一个精子使卵子受精。
- In human reproduction,one female egg is usually fertilized by one sperm.在人体生殖过程中，一个精子使一个卵子受精。
3 evolutionary
adj.进化的；演化的，演变的；[生]进化论的
- Life has its own evolutionary process.生命有其自身的进化过程。
- These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。
4 genes
n.基因( gene的名词复数 )
- You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
- Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
5 mince
n.切碎物；v.切碎，矫揉做作地说
- Would you like me to mince the meat for you?你要我替你把肉切碎吗？
- Don't mince matters,but speak plainly.不要含糊其词，有话就直说吧。