Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.astronet.ru/db/xware/msg/1227431
Дата изменения: Mon Apr 21 10:32:20 2008
Дата индексирования: Fri Jan 16 05:22:54 2009
Кодировка:

Поисковые слова: jet
Bacteriophages: The Most Common Life Like Form on Earth
Astronomy Picture of the Day
    


Bacteriophages: The Most Common Life Like Form on Earth
<< Yesterday 21.04.2008 Tomorrow >>
Bacteriophages: The Most Common Life Like Form on Earth
Credit: Wikipedia; Insert: Mike Jones
Explanation: There are more bacteriophages on Earth than any other life-like form. These small viruses are not clearly a form of life, since when not attached to bacteria they are completely dormant. Bacteriophages attack and eat bacteria and have likely been doing so for over 3 billion years ago. Although initially discovered early last century, the tremendous abundance of phages was realized more recently when it was found that a single drop of common seawater typically contains millions of them. Extrapolating, phages are likely to be at least a billion billion (sic) times more numerous than humans. Pictured above is an electron micrograph of over a dozen bacteriophages attached to a single bacterium. Phages are very small -- it would take about a million of them laid end-to-end to span even one millimeter. The ability to kill bacteria makes phages a potential ally against bacteria that cause human disease, although bacteriophages are not yet well enough understood to be in wide spread medical use.


January
February
March
April
May
June
July
August
September
October
November
December
 < April 2008  >
Mo Tu We Th Fr Sa Su

123456
78910111213
14151617181920
21222324252627
282930



Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.

Based on Astronomy Picture Of the Day

Publications with keywords: Earth - life
Publications with words: Earth - life
See also:
All publications on this topic >>