三级aa视频在线观看-三级国产-三级国产精品一区二区-三级国产三级在线-三级国产在线

您現在的位置: > Language Tips > Audio & Video > Special Speed News  
 





 
Genetic map points way to an improved honey bee
[ 2006-11-30 09:20 ]

This is the VOA Special English Agriculture Report.

Scientists now have a genetic map of the world's most important insect -- important to the food supply. The results showing the order, or sequence, of 98 percent of the honey bee genome created a buzz of excitement. Understanding how a honey bee is designed should help scientists produce stronger bees.

Honey bees are the world's major source of pollination for food, fiber and oilseed crops. Bees gather nectar from flowers; the liquid gives them food and material to make honey. As they land, their bodies pick up and drop off fine particles of pollen. Most flowering plants need pollination to reproduce.

But Kevin Hackett, an official at the United States Department of Agriculture, noted that the world's honey bee population is decreasing. He called the sequencing of its genome a powerful tool for fighting back against the causes.

One cause is the varroa mite which can kill young bees even before they leave their eggs. Another is the tracheal mite which nests in the breathing tube of adult bees.

Some people think that insect poisons have also played a part in reducing bee populations.

Experts say honey bees are responsible for as much as 20,000 million dollars worth of food production in the United States alone. But scientists have estimated that the bee population in the United States fell by 50 percent over the past half-century.

The main results of the Honey Bee Genome Sequencing Project Consortium appeared in the journal Nature. This international team is led by human-genome researchers at Baylor College of Medicine in Houston, Texas. Related reports appeared in other publications.

Like humans, bees have genes that give them a sense of day and night. Scientists believe this helps honey bees gather food.

Bees find flowers by smell. Bees have more genes for a sense of smell than other insects whose genes have been mapped. But one of the project scientists noted they have fewer genes for taste. He thinks this might help them avoid pesticides and plant diseases to find food.

The genetic research suggests that honey bees came from Africa. Their brains have similar genetic parts as the fruit fly. But fruit flies like to be alone. Scientists are interested in how, over millions of years, honey bees developed the complex social order in which they live.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. I'm Steve Ember.


pollination : 授粉

nectar : 花蜜


點擊進入更多VOA慢速


(來源:VOA  英語點津姍姍編輯)

 
 
相關文章 Related Stories
 
Cheese culture grows in Vermont Saving historic barns
         
 
 
 
 
 
         

 

 

 
 

48小時內最熱門

     

本頻道最新推薦

     
  Genetic map points way to an improved honey bee
  Laughter linked to health, happiness
  很“爵士”:至高無上的愛
  《絕望主婦》1(精講之二)
  NATO prepares for 2008 expansion

論壇熱貼

     
  福娃英文名更改,為何事先不考慮好?
  男扮女裝,女扮男裝?
  請教高人:關于社保方面的詞匯
  評頭論足之妙語連篇
  常用英語口語1000句
  翻譯:老鄉見老鄉,兩眼淚汪汪




主站蜘蛛池模板: 国产97在线观看 | 成人五级毛片免费播放 | x8x8女性性爽免费视频 | jiz欧美高清 | 国产成年人在线观看 | 欧美一级毛片免费看高清 | 日韩欧美综合视频 | 黄色一级欧美 | 国产精品每日在线观看男人的天堂 | 国产黄频 | 亚洲制服丝袜在线播放 | 黄色一级在线观看 | 国产资源在线观看 | 国产精品盗摄一区二区在线 | 日韩亚洲一区中文字幕 | 国产一级做a爰片久久毛片99 | 特级片免费看 | 女人被狂躁的视频免费一一 | 在线网站cosplay福利视频 | 手机在线观看视频你懂的 | 精品麻豆视频 | 欧美人成人亚洲专区中文字幕 | 国产精品卡哇伊小可爱在线观看 | 亚洲主播 | 亚洲自偷精品视频自拍 | 成人免费视频一区二区三区 | 国产 欧美 日产久久 | 日韩日日日 | 精品一区二区久久久久久久网站 | 国产精品久久九九 | 非洲特黄一级毛片高清视频 | 国产精品国产精品国产三级普 | 国产高清国内精品福利99久久 | 日韩欧美一区二区在线 | 日韩久久网 | 人妖与黑人做爰 | 久久久精品久久久久久久久久久 | 日本黄色生活片 | 激情亚洲视频 | 1024国产基地| 国产成人精品免费视 |