by Joseph Alexander 25,497 views
An animation depicting how odorants bind to olfactory receptors and trigger smell signals.
Created for Leslie Vosshall, The Rockefeller University. Created by Joseph Alexander. All copyrights reserved by Vosshall/Rockefeller University. This is shown solely for portfolio purposes. Duplication or public dissemination is strictly prohibited.
by dan izzo 44,128 views
The taste centers are in the cortex and in the thalamus of the brain. The organ of taste is the tongue. The surface of the tongue is covered with thousands of tiny fronds or papillae, which give it a velvety sheen. The taste buds, the primary organs of taste, are found within these papillae. There are four type of papillae-filiform, fungiform, foliate and vallate. Filiform and fungiform papillae are found on the front half of the tongue, and foliate papillae at the back. Filiform are threadlike in shape and more numerous than the mushroom-shaped fungiform type. Vallate papillae form a V across the back of the tongue. The base of the tongue is devoid of papillae, but is covered with nodules of lymphoid tissue, which make up the lingual tonsil. A taste bud consists of taste cells, with hairs that project into the moats surrounding the papillae, supporting cells and nerves. The salivary glands are connected by nerves to the taste buds. Stimulation of the taste buds stimulates the salivary glands to produce saliva.
by chichin85 59,883 views
If you can't smell, you probably can't taste very well either. They are closely related functions.
Receptor cells for taste and smell are located in the mouth and nose, respectively.
As the receptor cells are stimulated, they send impulses from these organs to the brain's smelling and tasting centers, the cortices.
For taste, impulses stimulated by the chemical compounds in food are sent to the gustatory cortex.
For smells impulses stimulated by the chemical compounds in odors are sent to the olfactory cortex.
As new compounds stimulate the receptors, the brain forms an odor memory bank so that it can recall the odors the next time they are present.
by dan izzo 13,004 views
7 Receptors of Smell
Seven primary odors may exist from which all other smells are derived. Classification of these primary odors is difficult since its is extremely hard to achieve objective testing. One classification suggests that the seven primary odors are: camphoraceous, like that of mothballs; musky, like that of anelica roots; floral, like that of a rose; pepperminty, like that of peppermint; ethereal, like that of nail polish; pungent, like that of a lemon; and putrid, like that of sulfurous eggs. Before a chemical can be smelled, it has to be volatile to diffuse into the air. It also has to be slightly water soluble to dissolve in the mucus that coats the olfactory epithelium, and it must be fat soluble to enter the cilia of the receptor cells.
by dan izzo 72,240 views
The Olfactory Pathway
Air inhaled through the nose passes over the olfactory membranes, where chemicals that are in the air stimulate the numerous olfactory receptor cells. The smell information passes from the receptor-cell neurons to the bulbs and tracts of the first cranial nerve, which pass into the frontal lobes of the brain. Each tract divides into medial and lateral striae, which pass the information to the olfactory cortex, where smell is perceived.