男女羞羞视频在线观看,国产精品黄色免费,麻豆91在线视频,美女被羞羞免费软件下载,国产的一级片,亚洲熟色妇,天天操夜夜摸,一区二区三区在线电影
首 頁 | 新聞英語 | 視聽英語 | 翻譯園地 | 實用英語 | 專欄作家 | 奧運英語 | 新詞新譯 | 書友天地 | 輕松英語  | 凈臉聯盟 | 英語論壇 | 少兒英語
您現在的位置: En_language tips > 輕松英語 > 一問到底 Dec 26, 2005
 





  Why does hair turn gray?

   
  Gray hair
   
  Why does hair turn gray?
Hair goes gray because pigment cells in the hair base at the roots of the hair stop producing melanin.

It doesn't matter if you are fair-haired or dark-haired you have the same chances of getting gray hair. However, it is more noticeable in darker haired people.

Graying of the hair generally starts at the age of around 30 for males and 35 for females however since the onset of this phenomena varies greatly from person to person, age is not the most accurate indicator.

The graying of hair appears to be genetically determined but the connection isn't at all clear.

So for now, your hair turning gray is just one of those mysteries of science that we have yet to solve. But salt and pepper hair always did look distinguished.

 

note:

pigment: 色素
melanin: 黒色素

 

 

 

onset: 開始

 

 



salt and pepper: 黑白相間而呈灰色的

 
 
 
Copyright by chinadaily.com.cn. All rights reserved
版權聲明:未經中國日報網站許可,任何人不得復制本欄目內容。如需轉載請與本網站聯系。
None of this material may be used for any commercial or public use. Reproduction in whole or in part without permission is prohibited.
主站蜘蛛池模板: 涡阳县| 玉田县| 泗水县| 太仓市| 小金县| 福海县| 聂拉木县| 灵川县| 潜山县| 扎兰屯市| 郁南县| 昌吉市| 收藏| 安吉县| 阿勒泰市| 犍为县| 临洮县| 滦南县| 南投市| 松原市| 金乡县| 汝城县| 信宜市| 天峨县| 安泽县| 柯坪县| 平果县| 泰宁县| 彝良县| 武强县| 梁山县| 上犹县| 南郑县| 博乐市| 麻阳| 聂拉木县| 垫江县| 郁南县| 扶沟县| 伊宁市| 屏山县| 双流县| 文水县| 鹿泉市| 民权县| 诸城市| 宣化县| 苏尼特左旗| 丁青县| 礼泉县| 沙雅县| 大城县| 白河县| 丹江口市| 西安市| 兴安县| 保德县| 万山特区| 丹巴县| 定陶县| 本溪市| 德阳市| 文登市| 泸定县| 巢湖市| 永兴县| 远安县| 衡南县| 罗平县| 渭源县| 天祝| 承德县| 泰和县| 凌海市| 阳泉市| 西城区| 郁南县| 新宁县| 德惠市| 石楼县| 新蔡县| 防城港市|