Electroplax
The electroplax , eplax for short , is an organ of some fish that generates electrical voltages that can be given off to the water or other living beings. There are around 250 species of fish that use the electroplax. These include electric eels , electric rays and electric catfish . The Elektroplax can generate voltages of up to 860 V. The achievable current strength can be up to 50 A, whereby this extreme could only be proven in the case of the spotted electric ray and also only at a voltage of 60 V.
construction
The electrical organs consist of muscle fibers that can no longer contract: the "electrical plates" . These plates are papillary on one side, but smooth on the other. There are synapses on this side . Several thousand of these plates are arranged in series in columns. These series result in very high voltage values. The strength of the current is determined by the number of parallel columns.
An exception is the electric organ of the dither catfish ( Malapterurus electricus ). The electrically active cells have evolutionarily of glandular cells of the skin developed, but work on a similar principle.
function
The release of acetylcholine leads to the excitation of the electroplaxis cell. Since this happens at the same time in almost all Elektroplax cells, voltages of up to 860 V build up for a short time, which discharge suddenly when the prey is touched and thus paralyze the prey.
meaning
The electroplax is used to paralyze prey and repel enemies. The power surges also serve as orientation in the murky water, to demarcate territories and to find reproductive partners.
Web links
- Electric fish: Signal generation & reception (PDF; 764 kB)
Individual evidence
- ↑ Amazon Shocker Facts . In: Nat Geo WILD . June 6, 2014 ( nationalgeographic.com [accessed December 9, 2016]).