Gustation: sense of taste
Gustatory hair
A single one of these projects from each gustatory receptor cell to the external surface through the taste pore.
Olfactory, tactile
All other flavors, such as chocolate and coffee, are combinations of the five primary tastes plus these accompanying sensations.
Taste pore
An opening in the taste bud.
Tastants
Chemicals that stimulate gustatory receptor cells. Once dissolved in saliva, it can enter taste pores and make contact with the plasma membrane of the gustatory hairs.
Taste buds
Each is an oval body consisting of three types of epithelial cells.
Filiform papillae
Elevations on the entire surface of the tongue which contain touch receptors but no taste buds.
Vallate papillae
Elevations that form an inverted V shaped row at the back of the tongue.
Sour, sweet, bitter, salty, umami
Five primary tastes that can be distinguished
Medulla oblongata
From taste buds, impulses propagate along the cranial nerves here.
Thalamus
From the Medulla, other axons carrying taste signals projects here.
Limbic system, hypothalamus
From the medulla, some axons carrying taste signals project here.
Taste buds
Most of the nearly 10,000 of a young adult are on the tongue, but some are also found on the roof of the mouth, pharynx, and epiglottis.
Fungiform papillae
Mushroom shaped elevations scattered over the entire surface of the tongue.
Olfactory receptors
Odors from food can pass upward from the mouth into the nasal cavity where they stimulate these.
Gustatory receptor cells
Separate receptor cells. They do not have an axon but rather synapse with dendrites of the first-order sensory neurons of the gustatory pathway.
Basal cells
Stem cells that produce supporting cells, which then develop into gustatory receptor cells that have a life span of about 10 days.
Papillae
Taste buds are found in these elevations on the tongue which provide a rough texture to the upper surface of the tongue.
Primary gustatory area
Taste signals that project from the thalamus to this area in the parietal lobe of the cerebral cortex give rise to the conscious perception of taste.
Taste aversion
The phenomenon in which people and animals quickly learned to avoid a food if it upsets the digestive system.
Taste buds
The receptors for taste sensations are located in these. Their number declines with age.
Gustatory receptor cell
The result of a tastant making contact with the gustatory hair is an electrical signal that stimulates release of neurotransmitters molecules from this cell.
Otorhinolaryngology
The science that deals with the ears, nose, and throat and their disorders.
Gustation
The sense of taste.
Supporting cells, gustatory receptor cells, basal stem cells
The three types of epithelial cells of each taste bud.
Nerve impulses
These are triggered when neurotransmitter molecules bind to the receptors on the dendrites of the first-order sensory neuron. Dendrites branch profusely and contact many gustatory receptors and several taste buds.
Supporting cells
These taste bud cells surround about 50 gustatory receptor cells.
Umami
This taste is described as "meaty" or "savory".
Facial (VII), glossopharyngeal (IX), vagus (X)
Three cranial nerves that contain axons of first-order gustatory neurons that innervate the taste buds.
