Ventral nerve cord
- Ventral nerve cord
The ventral nerve cords make up the
nervous system of some phyla of theinvertebrate s particularly within thenematode s,annelid s and thearthropod s. It usually consists ofcerebral ganglia anteriorly with the nerve cords running down the ventral ("belly", as opposed to back) plane of the organism. This characteristic is important in qualifying the difference compared to thechordate s which have adorsal nerve cord .Ventral nerve cords from
anterior toposterior (the thoracic and abdominaltagma in the arthropods) are made up of segmented ganglia that are connected by a tract of nerve fibers passing from one side to the other of the nerve cord called commissures [http://medical-dictionary.thefreedictionary.com/commissures] . The complete system bears some likeness to a ropeladder . In some animals the bilateral ganglia are fused into a single large ganglion per segment. This characteristic is found mostly in theinsect s.ee also
*
Protocerebrum
*Deutocerebrum
*Tritocerebrum References
*cite book |last=Hickman |first=Cleveland |coauthors=Roberts L. Keen S. Larson A. Eisenhour D|title=Animal Diversity |edition=4th |publisher=McGraw Hill |location=New York|language=English |isbn=978-0-07-252844-2
External links
* [http://www.prokop.co.uk/Research/Drosi-Info/nerve-cords.html Comparison of spinal cord and ventral nerve cord]
* [http://www.lobsters.org/tlcbio/biology6.html Nervous system of a lobster]
* [http://www.entomology.umn.edu/cues/4015/morpology/ Insect morphology]
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Look at other dictionaries:
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