在线国产一区二区_成人黄色片在线观看_国产成人免费_日韩精品免费在线视频_亚洲精品美女久久_欧美一级免费在线观看

您現在的位置: Language Tips> Easy English> Odd Question  
 





 
鹿角為什么會脫落
[ 2007-07-16 17:37 ]

在動物世界中,鹿是唯一能再生完整的身體零部件的哺乳動物。當鹿角長到最大尺寸后,骨頭開始變硬,像天鵝絨一樣柔軟的鹿茸開始脫落。一旦鹿茸掉光,就剩下赤裸的骨頭,就可成為角斗中的強大武器。在交配期結束時,鹿角脫落以保存能量,等到春天來臨,在其頭頂上就能長出一對新的隆起的組織骨結節。

Deer shed their antlers annually as apreludeto the regeneration, or re-growth, of new ones.

The entire shedding process takes a mere two to three weeks to complete, and the re-growth phase takes place over the summer. Thedocilemale deer that, with the exception of the male and the female reindeer, solelysportsantlers, sheds them between January and April, after the autumnmatingseasondraws to a close. He can do without antlers at this time, because his need for them in prior months, to attract and to impress females for hisharemof mates, and to fight with his competitors for the females' affections, no longer exists.

The antlers themselves differ from the hollow horns of cattle, in that they comprise solid bone tissue with a honey combed structure.Pedicles, orknobby, skin-coverednubsprotruding from the skull, support the deer's antlers, or points, which range in number from one shaft to eleven branches. The pedicles are a permanent fixture on the deer's forehead, and are the point from which the antlers annually break off.

During the first year the pedicles appear on the young deer's forehead. The following year, the youngster sprouts straight, spike-like shafts, and in the third year, the first branch appears. In successive years, as the deer matures, his antlers lengthen and, in most species, he acquires additional branches. One can actually determine the age of the deer from the number of branches on his antlers, as their number increases with age.

During the growth phase of the bony antlers, they are covered with a sensitive skin referred to as "velvet", which is filled with blood vessels that feed the antlers the vitamins and the minerals necessary to build up the bone, and to promote normal antler growth. Antler growth spans two to four months, after which time the velvet is no longer needed, and a ring, which effectively serves as a shutoff valve, forms at the base of the antlers and cuts off the blood supply to the velvet. As a result, the velvet withers, dries up, and falls off, often assisted by the deer, which rubs his antlers against tree bark. The antler regeneration is complete, and the shedding cycle will resume once mating season in the fall concludes.

prelude: 前奏
docile: 溫順的
sport
: 炫耀,賣弄
mating: 交配
draw to a close: 漸近結束
harem: 一群雌動物
pedicle: 肉莖
knobby: 多節的
nub: 小塊
velvet: 天鵝絨

(來源:coolquiz.com 英語點津 Annabel 編輯)

我想了解更多趣味百科知識

 
 
相關文章 Related Stories
 
         
 
 
 
 
 
         
 
 

48小時內最熱門

     
  女孩的心思誰能猜:Suspended from class
  各種各樣的“錢”
  “搶鏡頭”怎么說
  姚明婚后打算:備戰奧運第一

本頻道最新推薦

     
  為什么畢業時要穿學位服
  We cats can use chopsticks, too!
  不受歡迎的夜半歌聲:打鼾
  US Independence Day(美國國慶日)
  Exercise after dinner

論壇熱貼

     
  “低生育,素質好,男女都是寶”,怎么譯為好?請教高手!
  請問“老鄉”這個詞怎么翻譯?
  C-E: how to say "路盲"?
  各位,“相親”英語怎么說?
  指紋上的ridges and loops是什么意思?
  請教一下 餃子的“餡” 用English怎么說啊






主站蜘蛛池模板: 亚洲成人激情在线观看 | 亚洲毛片网站 | 一级黄色录像免费观看 | 波多野结衣 一区二区 | 日韩亚洲视频在线观看 | 欧美一区二区在线 | 中文字幕在线网址 | 日韩视频一区 | 在线精品亚洲 | 成人免费高清视频 | 天天射射天天 | 日韩精品一区二区三区 | 日本欧美日韩 | 欧美一区二区精品 | 久草在线在线精品观看 | 成人av国产 | 日韩毛片免费在线观看 | 欧美成人a∨高清免费观看 99精品欧美一区二区三区 | 久久久久国产精品视频 | 欧美视频在线一区 | 国产在线拍揄自揄拍视频 | 天天综合91| 国产精品一区自拍 | 羞羞网站免费 | 中文字幕一区二区在线观看 | 亚洲伊人久久网 | 亚洲热在线观看 | 亚洲欧美综合精品久久成人 | 国产黄色在线免费看 | 久久久久免费精品视频 | 欧美国产高清 | 国产一区亚洲 | 久久久国产精品入口麻豆 | 欧美一性一交 | 久久亚洲婷婷 | 国产激情在线 | 国产成人精品大尺度在线观看 | 呦一呦二在线精品视频 | 日日摸日日爽 | 成人看片毛片免费播放器 | 日韩在线视频第一页 |