Chemical Senses Flashcards
lowest of the taste thresholds
bitter
highest of the taste thresholds
sweet
taste bud cells are replaced about every ___ days
10
primary afferent in taste buds are:
group III small myelinated nerve
(with cell body in cranial nerve ganglion
what is the taste pathway for the front 2/3 of the tongue?
chorda tympani to facial (VII)
-geniculate ganglion
what is the taste pathway for the back of tongue and throat?
glossopharyngeal (IX) and vagus (X)
-petrosal and inferior vaal (nodose) ganglia
where does the taste pathway from the facial, glossopharyngeal, and vagus nerves go to?
to solitary nucleus and tract of medulla
from the solitary nucleus, where can the taste pathways continue? (3 options)
- to ventral posterior medial nucleus of the thalamus (VPL)
- to salivatory nuclei (VII, IX) for taste reflexes
- to hypothalamus/ amygdala
where does the taste pathway that runs from solitary nucleus to VPL of thalamus continue on to?
perceptual path ends at lateral surface of parietal cortex (Broadmann areas 3, 2, 1)
-adjacent to tactile area for tongue
where do the taste pathways for taste reflexes travel from the solitary nucleus to?
to salivatory nuclei (VII, IX)
the taste pathway from solitary nucleus to the hypothalamus and amygdala travels via ______
paraprachial nucleus of the pons
what is unique about the olfactory receptor cells?
same cell is receptor and nerve fiber cell body (no separate ganglion)
what second messenger systems do olfactory epithelium use?
probably uses cAMP or cGMP
for transduction of olfactory signals, where are the membrane receptors located?
on cilia
olfactory transduction AP travels via
unmyelinated fiber (CNI)
primary afferent group of olfactory transduction is
group IV axon
where do olfactory transduction signals pass through in bundles?
through the cribriform plate
fascicles of olfactory nerves (CNI) penetrate cribriform plate to enter:
olfactory bulb
what does the olfactory bulb do in the olfactory pathway?
it processes and relays information (2nd order fiber) into the lateral and medial olfactory tracts
the olfactory tract goes to the olfactory cortex on the ______ (what area)
parahippocampal gyrus (Broadmann area 28)
does the olfactory pathway have direct connection with the sensory thalamus?
no
