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: 股票| 桂平市| 江津市| 白银市| 栾川县| 西平县| 保山市| 广东省| 宜兰市| 东兰县| 台中市| 扎兰屯市| 定州市| 金门县| 榆树市| 同江市| 民勤县| 开封县| 随州市| 宿迁市| 凉城县| 七台河市| 陈巴尔虎旗| 剑川县| 明溪县| 永靖县| 密山市| 灵山县| 蚌埠市| 衡东县| 皮山县| 砀山县| 姚安县| 瑞安市| 寿宁县| 泰兴市| 吕梁市| 贵德县| 临江市| 新民市| 江永县| 诸暨市| 巴青县| 抚州市| 江油市| 凤城市| 武强县| 青州市| 电白县| 哈巴河县| 龙里县| 衢州市| 临城县| 蒲城县| 台山市| 上饶县| 策勒县| 云安县| 阜南县| 罗江县| 沙雅县| 昌黎县| 五大连池市| 香格里拉县| 调兵山市| 建德市| 临潭县| 务川| 郓城县| 平湖市| 天峻县| 衢州市| 舒兰市| 沅江市| 清水河县| 黄龙县| 苏尼特右旗| 房产| 天气| 天祝| 昂仁县| 韶山市|