Chemical Senses Flashcards
Which channels are activated by temperature and spicy foods?
TRP channels
What is the lowest concentration at which humans can detect odorants?
10^-14 M
Condition involving selective olfactory defecits?
Anosmias
What is the function of the Vomeronasal organ?
Detection of pheremones in animals.
Which glands secrete mucus into the nasal cavity?
Bowman’s Glands
How often do olfactory receptor cells turn over?
6-8 weeks
What are the 4 areas where the olfactory nerve projects?
- Piriform Cortex
- Olfactory Tubercle
- Amygdala
- Entorhinal Cortex
Where do fibers from the piriform cortex project and what is their function?
Orbitofrontal cortex for olfactory perception and identification.
Where do fibers from the olfactory tubercle project and what is their function?
Thalamus, for olfactory perception and identification.
Where do fibers from the amygdala project and what is their function?
Hypothalamus for motivation/emotion
Where do fibers from the entorhinal cortex project and what is their function?
Hippocampal formation, for olfactory memories.
What has increased sensitivity during an emotional state activated by epinephrine?
Olfactory receptors.
What has increased sensitivity when your hungry?
Locus Ceruleus activates the olfactory bulb.
What are the 3 types of papillae on the tongue and where are they?
Fungiform –> anterior tongue
Foliate –> Lateral aspect of tongue
Vallate –> in a “V” pattern on posterior tongue
Which nerves innervate the taste buds?
Facial, glossopharyngeal, vagus.
Where is taste information projected?
Ventral Posterior Medial Nucleus of the thalamus.
What channels are on salt taste buds?
Amiloride sensitive Na+ Channels
What channels are on sour taste buds?
H+ activated channel
What channels are on bitter taste buds?
TR2 G protein Coupled Receptor
What channels are on sweet taste buds?
G protein coupled receptor
What hormones are elevated with increased appetite, and increase taste receptor sensitivity?
Serotonin and cholecystokinin (CCK)
What hormones increase olfactory cell response to salt?
Aldosterone and vasopressin
What is the order of projections of taste information?
- ) Nucleus of solitary tract.
- ) Ventral Posterior Medial Nucleus of Thalamus.
- ) Gustatory cortex at insula.
What is the name of the property alowing the gustatory cortex neurons to each respond to different tastes?
Across fibre pattern.
