olfactory nerve


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Related to olfactory nerve: optic nerve, Cranial nerves

olfactory

 [ol-fak´tŏ-re]
pertaining to smell.
olfactory nerve the first cranial nerve; it is purely sensory and is concerned with the sense of smell. The nerve cell bodies are situated in the olfactory area of the mucous membrane of the nose. The nerve fibers lead upward through openings in the ethmoid bone, connect with the cells of the olfactory bulb, and then pass inward to the cerebrum. See Appendix 2-5.

olfactory nerve

n.
Either of the first pair of cranial nerves that conduct impulses from the mucous membranes of the nose to the olfactory bulb.

olfactory nerve

one of a pair of nerves associated with the sense of smell. They are composed of numerous fine filaments that ramify in the mucous membrane of the olfactory area. The fibers of the olfactory nerve are nonmedullated and unite into fasciculi that form a plexus under the mucous membrane and rise in grooves or canals in the ethmoid bone. The fibers pass into the skull and form synapses with the dendrites of the mitral cells. The area in which the olfactory nerves arise is situated in the most superior part of the mucous membrane that covers the superior nasal concha. The olfactory sensory endings are modified epithelial cells and the least specialized of the special senses. The olfactory nerves connect with the olfactory bulb and the olfactory tract, which are components of the part of the brain associated with the sense of smell. Also called first cranial nerve, nervus olfactorius.
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Olfactory nerve
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RIGHT OLFACTORY NERVE

olfactory nerve

A sensory nerve with neuronal cell bodies located in the olfactory epithelium (a yellowish-brown thickened patch of epithelium found along the upper back walls of the nasal cavity). Axons from the receptor cells join into approximately 20 small nonmyelinated bundles (the olfactory nerves). These nerves pass into the skull through holes in the cribriform plate of the ethmoid bone and terminate in the ipsilateral olfactory bulb in spherical synaptic structures called glomeruli.
Synonym: first cranial nerve See: cranial nerveillustration
See also: nerve

olfactory

pertaining to the sense of smell.

olfactory bulb
the bulblike extremity of the olfactory tract on the rostral surface of the frontal lobe of each cerebral hemisphere; it is lodged against the cribriform plate through which the olfactory nerves pass.
olfactory glands
in the mucosa of the nasal olfactory region; branched tubuloalveolar glands secreting serous fluid; cleanse the mucosal surface, dissolve odor-producing substances.
olfactory hair
modified cilia projecting from olfactory cells in the mucosa of the nasal olfactory area.
olfactory mucosa
specialized olfactory cells in a region of nasal mucosa covering ethmoturbinates, turbinates and nasal septum.
olfactory nerve
the first cranial nerve made up of about 20 bundles and concerned with the sense of smell. The cell bodies are situated in the olfactory mucous membrane of the nose. Nerve fibers lead upward through openings in the cribriform plate of the ethmoid bone and connect with the cells of the olfactory bulb. From there the fibers pass inward to the cerebrum. See also Table 14.
olfactory neuroblastoma
rare neoplasm, commonest in pups and kittens, characterized by local invasion of surrounding bone.
olfactory pit
primordia of the nasal cavities commencing as pits in the olfactory placodes of the embryo. The pits deepen and finally open into the oral cavity as the choanae; the external orifices become the nostrils. Called also nasal pit.
olfactory system
includes the olfactory part of the nasal mucosa, the olfactory nerves and the olfactory bulbs of the cerebrum.
olfactory tract
a band of white nerve fibers visible on the ventral surface of the brain running caudally from the olfactory bulbs.
olfactory tractotomy
surgical removal or transection of the olfactory tracts to produce an anosmia may be performed in cats as a means of controlling spraying and inappropriate urination.
References in periodicals archive ?
Rows of cells that appear to enter the procerebrum from the olfactory nerve suggest that they form the columns of neurons reported in the procerebrum (Zaitseva, 2000).
Although the physiologic and morphologic effects of NYT and its components have been reported, little is known about the effect of NYT on olfactory nerve function.
In the olfactory nerve, OECs surround large numbers of nonmyelinated axons and normally do not form myelin [38].
Thus, although ionic bloodborne Mn can contribute to increased Mn levels in some brain regions, translocation of solid Mn oxide UFPs from nasal deposits to CNS regions via the olfactory nerve should not be excluded as a possible mechanism.
Prominent anti-caspase-3 staining was also present in olfactory nerve bundles (axons of OSNs) in the underlying lamina propria of the mice instilled with SG.
They fill the olfactory nerve terminals of the three-toed box turtle with a fluorescent dye, apply pulses of odor, and produce a map representing the location of the glomeruli responding to the odor, as well as the amplitude of the response.
Scent receptors in the nose send chemical messages via the olfactory nerve to the limbic system - a primitive area of the brain that deals with basic emotions, including anger and fear, and memories.
It's thought that the health of the olfactory nerve, which sends smells from the nose to the brain, is a good indicator of overall health.
When these mice smelled the odor associated with the electrical shocks, the amount of neurotransmitter, chemicals that carry communications between nerve cells, released from the olfactory nerve into the brain was as big as if the odor were four times stronger than it actually was.
Previous hypotheses about the origin of these olfactory nerve cells have given credit to embryonic cells that develop into skin or the central nervous system, where ear and eye sensory neurons, respectively, are thought to originate.
And easy accessibility of nasal tissue makes noninvasive biopsy of olfactory nerve cells possible, noted Dr.
In humans, the sensory patches are one square inch which contains 10 million olfactory nerve cells.