What is flavor derived from?
What four things do we use our senses of taste and smell for?
- to decide what and whether to eat
- to decide whether we will care for our young
- to decide whether and with whom to mate
- to 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 epithelium
- 2. serus glands to wash away the odors from the OEp
- 3. 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 cells
- Supporting Cells
- Stem Cells
- Nerve 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 neurons
- 3. 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 weeks
- b/c of viruses, toxic particles, bacteria
Approximately how many receptor genes are there?
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 synapse
- Side 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 tongue
What are the 3 types of papillae?
Where are the gustation cells located in papillae?
- in fungiform: on the top of the papillae
- in foliate and circumvallate: on the sides of the papillae
What are the 3 types of cells in tastebuds?
- supporting cells
- receptor cells
- stem cells
How do taste cells stain?
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?
What type of receptors do salt receptors have?
What type of receptors do acid/sour cells have?
What type of receptors do sweet and/or bitter cells use?
G-coupled protein receptors
What do the so-called Umami receptors detect?
How does the map of different taste sensations of the tongue look?
it doesn't, no such map exists!!!!!