Final Pt. 2 Flashcards
Chemoreceptors respond to…
chemicals in aqueous solutions (saliva, nasal mucuos)
What are some features of olfactory cells?
replaced every 4-8 weeks, dendrite towards mucus (captures airborne odorants, few molecules activate cell)
What system do olefactory receptors use?
2nd messanger system to trigger ligand channels with Na, Ca
Where do olefactory APs synapse?
AP carried to olefactory bulbs, synapse on mitral cell
3 steps of olefactory transmission?
- Axons travel past cribiform plate/ ethmoid bone to reach olefactory bulb
- synpase w/ mitral cell to form olefcatory tract
- olefactory tract goes to limbic system and olefactory cortex
Sense of smell does not:
Pass through thalamus
In order to taste…
Much touch hairs on gustatory neurons
Binding of chemical depolarises membrane (generator potential to brainstem)
Taste is a…
complex sensory reception
What is a taisant?
odorant, binds to specialized receptors on gustatory hairs open graded potential, activates afferent fibers
what 2 facial nerves aide in taste?
Facial nerve (XII) and glossopharyngeal (IX)
What 4 cells make taste cells?
epithelial cells, gustatory cells (sensory taste) basal cells (stem cells), can sense touch and thermal
supporting cells (insulating receptor)
What do the microvilli is gustatory cells do?
extend through taste pore into salivia to detect chemicals
5 tastes correspond with what ions?
sweet- sugar, alcohol, amino acids (guslducin)
salt- metal ions (Na)
sour- hydrogen ions
bitter- alkaloids (nicotine, quintinko)
Umami- glutamate (amino acid)
Pathway of taste through facial nerves
facial and glossopharyngeal nerve take impulse to solidary nucleus of the medulla- thalamus- gustatory cortex- hypothalamus and limbic system
What influences taste?
80% smell, thermoreceptors and mechanoreceptors also influence taste