Re: Do electric eels have to touch someting to discharge electricity

Greetings,
This information was taken from the American Institute of Physics locate at

http://www.aip.org/radio/html/electric_eels.html
IN THE JUNGLES OF SOUTH AMERICA, IN THE MURKY WATERS OF THE AMAZON, LIVES
THE ELECTRIC EEL.  IT CAN GROW UP TO EIGHT FEET LONG, WEIGH ONE HUNDRED
POUNDS AND  ZAP ITS PREY WITH UP TO 600  VOLTS OF ELECTRICITY.  THAT'S FIVE
TIMES THE VOLTAGE THAT COMES OUT OF THE WALL SOCKET AND PLENTY STRONG
ENOUGH TO INJURE OR KILL A HUMAN.  THE EEL GETS ITS ELECTRIC CHARGE FROM A
LONG CHAIN OF SPECIAL CELLS THAT RUN  THE LENGTH OF ITS BODY.  THESE CELLS
ARE ADAPTATIONS OF STANDARD MUSCLE CELLS SAYS MOLECULAR PHYSIOLOGIST
JOHN DEDMAN AT THE UNIVERSITY OF CININNATI.

     Dedman: "all of our cells. . . have electrical currents going on all the 
time. . . The eel has. . . put
together individual cells that stack along the length of the animal, and each of 
the cells have the ability to
store a charge and hold it very much like a battery" 

     EACH OF THESE SPECIAL CELLS, CALLED ELECTROCYTES, CAN DISCHARGE ONLY 
A MEASLY EIGHTY MILLIVOLTS OF ELECTRICITY.  BUT PUT THOSE CELLS ALL IN A ROW
AND YOU GET A MUCH LARGER JOLT.  THIS IS TRUE WITH BATTERIES, TOO.  IF YOU'RE
NOT GETTING ENOUGH POWER WITH A SINGLE BATTERY, YOU CAN STRING THEM
ALONG IN A SERIES AND UP YOUR VOLTAGE.   A REALLY BRIGHT FLASHLIGHT, FOR
EXAMPLE, NEEDS A LONG HANDLE SO IT CAN HOUSE SEVERAL BATTERIES.   AND AN
EEL'S ELECTROCYTE CHAIN NEEDS TO BE REALLY LONG TO TURN ITSELF INTO A LIVE
WIRE, SAYS ICTHYOLOGIST PHYLLIS CAHN AT LONG ISLAND UNIVERSITY.
     
     Cahn: "there are about 6,000 of these electrocyteslined up in series as if 
you were to have 6000
batteries lined up." 

     THE TRICKY THING IS TO GET EACH CELL TO DISCHARGE ITS ELECTRICITY AT
THE SAME TIME.

     Dedman: "the eels have developed a mechanism of stimulating each 
electrocyte in a simultaneous
fashion so they all are activated at the same time and that provides for a 
single discharge for all the cells
and causes the high voltage." 

     WITH THE  MODIFICATION OF BASIC MUSCLE CELLS, THE EEL TURNS ITSELF INTO
A STANDARD ELECTRICAL CIRCUIT.  PEOPLE HAVE EVEN USED EELS TO LIGHT UP A
STRING OF LIGHT BULBS--BUT I WOULDN'T TRY IT AT HOME.   

Thanks for taking the time to send in a question to the Mad Sci Network.

June Wingert
Baylor College of Medicine
Houston, Texas