When the command is given, a complex array of nerves makes sure that the thousands of cells activate at once, no matter how far they are from the command nucleus. Each electrogenic cell carries a negative charge of a little less than millivolts on its outside compared to its inside.
When the command signal arrives, the nerve terminal releases a minute puff of acetylcholine, a neurotransmitter. This creates a transient path with low electrical resistance connecting the inside and the outside of one side of the cell.
Thus, each cell behaves like a battery with the activated side carrying a negative charge and the opposite side a positive one. Because the cells are oriented inside the electric organ like a series of batteries piled into a flashlight, the current generated by an activated cell "shocks" any inactive neighbor into action, setting off an avalanche of activation that runs its course in just two milliseconds or so.
This practically simultaneous start-up creates a short-lived current flowing along the eel's body. If the eel lived in air, the current could be as high as one ampere, turning the creature's body into the equivalent of a volt battery.
But eels live in water, which provides additional outlets for the current. They thus generate a larger voltage, but a divided, and therefore diminished, current. To my knowledge, there are no specific studies on why eels can shock other animals without shocking themselves but one possible explanation could be that the severity of an electric shock depends on the amount and duration of the current flowing through any given area of the body.
For the purposes of comparison, an eel's body has roughly the same dimensions as an adult man's arm. Their bodies contain electric organs with about 6, specialized cells called electrocytes that store power like tiny batteries. When threatened or attacking prey, these cells will discharge simultaneously. They live in the murky streams and ponds of the Amazon and Orinoco basins of South America, feeding mainly on fish, but also amphibians and even birds and small mammals.
As air-breathers, they must come to the surface frequently. They also have poor eyesight, but can emit a low-level charge, less than 10 volts, which they use like radar to navigate and locate prey.
Electric eels can reach huge proportions, exceeding 8 feet in length and 44 pounds in weight. They have long, cylindrical bodies and flattened heads and are generally dark green or grayish on top with yellowish coloring underneath. Human deaths from electric eels are extremely rare. However, multiple shocks can cause respiratory or heart failure, and people have been known to drown in shallow water after a stunning jolt.
All rights reserved. Common Name: Electric Eel. Scientific Name: Electrophorus electricus. Type: Fish. Diet: Carnivore. Group Name: Swarm. Size: 6 to 8 feet. Weight: 44 pounds. One sheet hosts red and blue dots. Salt water is the main ingredient in the red dots. The blue dots are made from freshwater. A second sheet has green and yellow dots. The green gel contains positively charged particles. The yellow gel has negatively charged ions. The red and blue dots on one sheet will nestle between green and yellow ones on the other sheet.
Those red and blue dots act like the channels in the electrocytes. They will let charged particles flow between the green and yellow dots. Just as in an eel, this movement of charge makes a tiny trickle of electricity.
And also as in an eel, a lot of dots together can impart a real jolt. In lab tests, the scientists were able to generate volts. The team reported its initial results in Nature last December.
The artificial organ is easy to make. Its charged gels can be printed using a 3-D printer. And as the main ingredient is water, this system is not costly. Even after being pressed, squished and stretched, the gels still work.
He led the study with Anirvan Guha. Both are graduate students in Switzerland at the University of Fribourg. They study biophysics, or how the laws of physics work in living things. Their team is collaborating with a group at the University of Michigan in Ann Arbor. For hundreds of years, scientists have tried to imitate how electric eels work. In , an Italian physicist named Alessandro Volta invented one of the first batteries.
LaVan did not work on the new study. But 10 years ago, he led a research project to measure how much electricity an eel produces.
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