- Ventral nerve cord
The ventral nerve cords make up the
nervous systemof some phyla of the invertebrates particularly within the nematodes, annelids and the arthropods. It usually consists of cerebralganglia 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 the chordates which have a dorsal nerve cord.
Ventral nerve cords from
anteriorto posterior(the thoracic and abdominal tagmain 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 rope ladder. In some animals the bilateral ganglia are fused into a single large ganglion per segment. This characteristic is found mostly in the insects.
*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
* [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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