vomeronasal organ

(redirected from Jacobsen's organ)
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vo·mer·o·na·sal or·gan

[TA]
a sense organ for pheromones in lower animals, usually regresses after the sixth month of gestation in humans; of debatable functional significance in humans when it does exist in vestigal form; located in a small canal, ending in a blind pouch, in the mucous membrane of the nasal septum, beginning just behind and above the incisive canal.

vomeronasal organ

(vō′mə-rō-nā′zəl)
n.
Either of two olfactory sense organs, found near the vomer in certain amphibians, reptiles, and mammals, that detect pheromones and other chemical compounds. In humans, these organs regress during fetal development. Also called Jacobson's organ.

vomeronasal organ

a structure on each side of the nasal septum believed to be a chemical sensory center for "sixth sense" detection of pheromones, carried by the nervous terminalis.

Jacobson,

Ludwig L., Danish anatomist, 1783-1843.
Jacobson anastomosis - a portion of the tympanic plexus.
Jacobson canal - a minute canal in the wedge of bone separating the jugular canal and carotid canal. Synonym(s): tympanic canaliculus
Jacobson cartilage - a narrow strip of cartilage located between the lower edge of the cartilage of the nasal septum and the vomer. Synonym(s): cartilago vomeronasalis
Jacobson nerve - Synonym(s): tympanic nerve
Jacobson organ - a fine vestigial horizontal canal ending in a blind pouch in the mucous membrane of the nasal septum. Synonym(s): vomeronasal organ
Jacobson plexus - a plexus on the promontory of the labyrinthine wall of the tympanic cavity, formed by the tympanic nerve, an anastomotic branch of the facial nerve, and sympathetic branches from the internal carotid plexus. Synonym(s): tympanic plexus
Jacobson reflex - flexion of the fingers elicited by tapping the flexor tendons over the wrist joint or the lower end of the radius.

vomeronasal organ

an organ thought to supplement the olfactory system in receiving pheromonic communication. The sensory part of the organ is in two long, thin sacs, situated on either side of the nasal septum at its base. The entrances to the sacs are from the incisive ducts which communicate with the nasal cavity and a pit in the roof of the mouth, just behind the dental pad or upper incisor teeth in horses. The function of the organ is probably related to the estrus-seeking action of flehmen. Called also organ of Jacobson.