Define gyrus. gyrus synonyms, gyrus pronunciation, gyrus translation, English dictionary definition of gyrus. n. pl. gyÂ·ri A rounded ridge, as on the surfaces of the cerebral hemispheres. n , pl gyri another name for convolution3 n., pl. gyâ¢ri a convoluted fold of...
olfactory nerve. n. Any of numerous olfactory filaments in the olfactory portion of the nasal mucosa that enter the olfactory bulb, where they terminate in synaptic contact with mitral cells, tufted cells, and granule cells. Also called first cranial nerve.he 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.
To get to the brain, the axons of the olfactory sensory neurons must get through the skull (see side view of the skull in Figure 1 on the left). The olfactory epithelium lines the bone of the part of the skull just above the nasal passages, and the axons of the neurons pass directly through tiny holes in this bone. type of spatial mapping also exists in the olfactory epithelium, in the nasal passages. Here, scientists have shown that certain volatile chemicals attach to receptor cells in defined patches of epithelium and not to others.