GS Gustatory Flashcards
what is the TFS for salty
0.01M
what is the TFS for sour
0.009M
what is the TFS for sweet
0.01M
what is the TFS for bitter
0.000008M
what four structures make up the tongue
taste buds, taste receptor, microvilli, papillae
where are taste buds located
groove like structures called papillae
each taste buds contain how many taste cells
50-100 taste cells
life span of mature taste buds
short lived
how and where are mature taste buds regenerated
continuously and from basal cells
apical microvilli of taste cells are exposed to saliva through where
the taste pore
tasty substances are sensed where
microvilli
taste substance is sensed at the microvilli and always induces what
depolarisation and action potential degeneration
taste cell action potential releases what
neurotransmitters
taste cell action potentials releases neurotransmitters which activates what
gustatory afferent fiber
different taste stimuli use different
signal transduction methods
salty sensing taste cells express what
amiloride-sensitive sodium channels
(ENaC sodium channels)
sour sensing cells express what
proton-sensitive potassium leak channels
sodium in salts enters through what
channel to depolarise the cell
sour is the taste of what ion
acid (H+)
Acid ions (H+) block what
potassium channels
when acidic ions block potassium channels what does this do
reduce the gK and depolarising the cell
potassium type salts also stimulate these cells because of
leak potassium channels and change in Ek
bitter sensing taste cells use what receptors, and what are they coupled to
7-TM receptors
Various G proteins
bitter sensation is a method for recognising what type of compounds
Toxic
what are the family of related bitter receptors
T2 receptors
when receptors couple to Gq what activates it
and what does it increase
PLC
increases Ca2+ through IP3
some receptors couple to gustducin which activates what
cyclic nucleotide phosphodiesterase’s
how do few bitter compounds work
directly blocking leaking potassium channels
sweet sensing cells use what receptors
and coupled to what
7-TM receptors
Gs
sugars act through what to produce cAMP
Gs
once cAMP is produced by sugars what does it do
PKA phsophorylates and closes potassium leak, causing depolarisation
artificial sweeteners bind receptors coupled to Gq which activate what
PLC to increase Ca2+ through IP3
coding for taste
1. what will the stimulus activate
2. which will activate what and where
stimulus will activate one specific receptor, which will activate only one specific pathway to the CNS
Pattern Code
1. stimulus will activate what
stimulus will activate all receptors in different manners and proportions, then CNS decodes the signal
taste cell neurons increase their firing rate with increases in what
stimulus concentration
responses from taste and smell are first combined in where
orbital frontal cortex
OFC also receives input from where
the primary somatosensory cortex and the inferotemporal cortex in the visual pathway
biomodal neurons in this area respond to what senses
taste and smell
taste and vision
firing of these neurons is also affected by what
the level of hunger of the animal for a specific food
