Module 15 - other sensory systems Flashcards
what type of recepotrs detect smell
olfactory sensory neurons
what is OSN pathway in insect
glomeruli in antennal lobe
then projection neurons which take it to
mushroom body (MB) and lateral horn (LH)
what is OSN pathway in mammals
glomeruli in olfactory bulb
then via mitral cells to the olfactory cortex
what are the lateral cells in olfaction (mammals)
periglomerular cells
granule cell
what type of receptors are olfactory receptors
GPCRs
what does odorant binding activate in the GPCR
GDP replaced with GTP
which activates adenylate cyclase
which converts ATP to cAMP
which activates cyclic nucleotide gated channel
which allows Ca2+ and Na+ through
which= depolarisation
how does combinatorial coding work
diff odorants acittvate various receptors activating many neurons
one diff between olfac and vision system
in vision the receptors are at the back
olfac reptors at front
what nerve do taste reeptor cells activate
gustatory nerve
what are the 3 tytpes of papillae
circumvallate (at back)
foliate (at sides)
fungiform (at tip)
what are the receptor type for umami, sweet and bitter
GPCRs
what are the specific GPCRs for umami and sweet
T1R1
T1R2
T1R3
what is receptor type for sour taste
TRP channels
what organ in vertabrates detetcs environmental chemical changes or pheromones
Vomeronasal organ
sends signals to hypothalamus
how is sound detected
variations in air pressure
how do insects detect sound
as speed of moving particles
normal human heaing range
20-20,000Hz
what frq waves travel furthwr
low frq waves
what are stereocillium on hair cells linked by
tip links
these are pushed by mechanical force which opens channel - allows K+ entry INWARDS
which NT is released in hair cells
glutamate
travels to spiral ganglion neuron
what is the tonotopy of the cochlea
apex is wider and less stiff = lower frq
base is thinner, shorter and more stiff = high frq
(think of harp strings)
name the 3 tiny ear bones
malleus
incus
stapes
what are the 2 components of vestibular system
semicircular canals
otolith organs
whatt do utricle and saccule detect
head acceleration and psotion
via CaCO3 crystals that dectect gravity and acceleration
