The ventral nerve cord makes up the nervous system of some phyla of the invertebrates, particularly within the nematodes, annelids and the arthropods. It usually consists of cerebral 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 the chordates, which have a dorsal nerve cord.
Ventral nerve cords from anterior to posterior (the thoracic and abdominal tagma 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 . 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.
Other articles related to "nerve, nerves, ventral":
... The cranial nerve nuclei schematically represented dorsal view ... in blue Nuclei of origin of cranial motor nerves schematically represented lateral view Cross section of the lower pons showing the facial motor nucleus and part of ... Reflex arc lower limb → 1° (Golgi tendon organ) → 2° (Ventral/anterior spinocerebellar tract→ SCP → Cerebellar vermis) upper limb → 1° (Golgi tendon organ) → 2° (Rostral spinocerebellar ...
... It consists of fibers arising from the ventral cochlear nucleus ... A collection of nerve cells inside forms a trapezoid nucleus ... Most nerve fibers pass directly from the superior olivary nuclei to the inferior colliculus ...
... of thalamus Thalamic reticular nucleus Taenia thalami Grey matter/ nuclei paired AN Ventral VA/VL VP/VPM/ VPL Lateral LD LP Pulvinar nuclei Metathalamus MG LG midline MD Intralaminar ... Reflex arc lower limb → 1° (Golgi tendon organ) → 2° (Ventral/anterior spinocerebellar tract→ SCP → Cerebellar vermis) upper limb → 1° (Golgi tendon organ) → 2° (Rostral ...
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