NS69:Histology of the Odor and Taste Receptors

What is flavor derived from?

TasteSmellMouth feeling

What four things do we use our senses of taste and smell for?

to decide what and whether to eatto decide whether we will care for our youngto decide whether and with whom to mateto assert our claim on territory

Where does the olfactory epithelium exist?

In a very small portion above the nasal conchae

What three things help us to determine the difference between OEp (olfactory epithelium) and CEp (ciliated epithelium)?

OEp have:1. large nerve bundles beneath the epithelium2. serus glands to wash away the odors from the OEp3. mucus glands to secrete mucus, which provides a medium for particles to dissolve in

What kind of cells make up the OEp: squamous, cubiodal, columnar?

None, we don't classify it

What are the 5 types of cells that exist in the OEp?

Nerve cellsSupporting CellsStem CellsGlandsNerve Cell Bundles

What do olfactory nerve cells have on their apical end to enhance olfaction?

9 +2 microtubule-arranged immotile cilia (b/c they are w/o certain accessory proteins)form dendritic like arrangement on the end of the olfactory cell

What three things make the olfactory nerve cell really unique?

1. They are the only nerve cell to serve both functions of recieving and transmitting the neural signal.2. They have stem cells that allow regeneration of neurons3. Each cell only does one smell. Therefore sense is hard-wired in the sensory organ and doesnot really have to be processed like all the other senses

How often do olfactorary neurons regenerate?Why must they regenerate so often?

days to weeksb/c of viruses, toxic particles, bacteria

Approximately how many receptor genes are there?

1000

What is the reasoning behind the one receptor type for each olfaction neuron cell?

b/c olfaction was first sense to develop evolutionarily, most primative

What type of receptors do most olfactorary cells have on them?

G-protein coupled receptors

What is a glomerulus?

Where several of the same receptor type neurons synapseSide Note: it's pretty amazing that they are able to do this considering all the challenges they face

What parts of the body are taste buds/papillae located on?

the tongueepiglottuspalatepharynx

What are the 3 types of papillae?

circumvallatefoliatefungiform

Where are the gustation cells located in papillae?

in fungiform: on the top of the papillaein foliate and circumvallate: on the sides of the papillae

What are the 3 types of cells in tastebuds?

supporting cellsreceptor cellsstem cells

How do taste cells stain?

Lighter

Where do the central processes of taste nerves enter and terminate at?

They enter in the solitary tract and terminate in the rostral solitary nucleus

What are the five different types of taste receptors?

SaltAcidsSweetBitterUmami

What type of receptors do salt receptors have?

Na+ channels

What type of receptors do acid/sour cells have?

H+

What type of receptors do sweet and/or bitter cells use?

G-coupled protein receptors

What do the so-called Umami receptors detect?

glutamate

How does the map of different taste sensations of the tongue look?

it doesn't, no such map exists!!!!!