Olfactory nerve

Olfactory nerve (nervus olfactorius) - I pair of cranial nerves, the only nerve end of the brain is formed by the protrusion of the wall brain bubble. As the optic nerve, olfactory nerve not homologous other cranial nerves.
Olfactory nerve - peripheral part of the olfactory analyzer begins in the olfactory region of the nasal cavity. The neurons of the first order are formed bipolar cells placed among the epithelial cells of the mucous membrane of the nose. Short peripheral extensions of these cells end up in the mucosa of the nasal cavity. Axons bipolar cells gather in the stem, the so-called olfactory thread (fila olfactoria), which through the holes perforated plate ethmoid (lamina cribrosa) penetrate into a cavity of a skull and included in the olfactory bulb (bulbus olfactorius). They end in the olfactory the glomeruli (glomeruli olfactorii), representing branching olfactory threads and dendrites mitral cells in the olfactory bulb. Mitral cells are olfactory neurons II order. Olfactory bulb - grey flattened body is about 1 cm long and 3-4 mm wide, located on the lower surface of the frontal lobe near the midline. The olfactory bulb, which closed the peripheral and Central olfactory path, consists of five layers, formed by the nerve fibers and cells. From the layer of mitral cells in the olfactory bulb starts Central olfactory path - the Central Department of the olfactory analyzer. The loss of smell, or anemia (see), is an important symptom defeat the base of the frontal lobe of the brain. It may also be associated with damage to the mucous membrane of the nose.