Sagittal cut of the head near the median plane, showing among others: Nasopharyngeal area, cerebrum, cerebellum, medulla oblongata, spinal column, pituitary gland, esophagus. Everything in front of a white background. The nose enables us to breathe and perceive scents that our brain analyzes. The nasal wings take turns every three or four hours, so that only one nostril breathes and smells at a time, whereas the other can rest.
The large amount of sensore (olfactory) cells are derive from the olfactory nerve. The olfactory mucosa also consists of basal and supporting cells that surround the sensory cells. Each one of the over 10 million cells has ca. five tiny olfactory hairs that are able to catch solute odorant molecules. When that happens, the sensory cells generates a nerve impulse. The nerve fibers lead into the olfactory bulb, from where the impulses are conducted to the several areas of the brain in which olfactory stimuli are consciously perceived. The olfactory bulb is part of the telencephalon, has the size of a match head, and is located near the ethmoid bone. The ethmoid bone, part of the central cranial base, contains tiny apertures for the fibers of the olfactory cells.
The outward part of the nose consists of bone and cartilage. The nasal bones constitue the form of the nose, whereas the cartilage makes it flexible. Each nasal cavity is divided into three ducts by nasal conchae. The paranasal sinuses are located behind the eyebrows, behind the cheeks, and in the triangle between forehead and nose.
