Lecture 10: Taste & Olfaction Flashcards
Flavour includes :
-____
-____
-____
Taste
Smell
Other nerve endings in mouth
__ is the sense of taste
Gestation
What are the tastes we perceive ?
Sweet, salty, sour, bitter, Unami
Taste molecules must dissolve in ___
Saliva
Individual receptor cells are ____
Chemoreceptors
Different tastings are traduced by different kinds of ____
Channels
Different tastings are transduced by different kinds of channels
_____: Na+ influx
______: H+ blocks K+ channels
______: Phosphorylation and block K+
_______: Inhibit phosphodiesterase , increase cAMP
______: Activation of mono alert -selective cation channel
Taste pathways in the CNS:
—-> At the ______
—-> in the ____
—-> in the _____
—-> To the ventro-posterior medial ___, ____ and ____
—-> to the ___ and ____ cortex
Tongue
Medulla oblongata
Pons
Thalamus, hypothalamus and amygdala
Insular and orbital
______ implies that the activity in one neuron type is both necessary and sufficient to represent a given sensory attribute
____ hypothesis proposes that the pattern of responses to a particular stimulus across all fibres is the central feature of coding
Labelled line
Across Fiber
____- Sense of smell
Olfaction
Number of human olfactory receptor cells = ____
Number of dog olfactory receptor cells =_____
5 million
4 billion
Surface area of olfactory epithelium in humans = _____
Surface area of olfactory epithelium in dogs = ____
10cm2
170cm2
garlic smell can indicate _____
Breath of a ________ smells like apples
________ from bacteria may smell like a wine cellar (musty)
Arsenic poisoning
Diabetic in a coma
Infection after surgery
________ are primary sensory neurons that generate action potentials
Olfactory receptor cells
Olfactory receptor cells have a life span of _____
30-60 days
Door is first detected at _____ of _____. If signal is strong enough, it will generate an ____ in the receptor neuron
Cilia of olfactory receptor neuron
Action potential
CNG channels =_________ channels
Cyclic - nucleotide - gated
The __ signal controls both excitation and adaptation
Ca2+
_____ adaptation - the Ca2+ signal controls both excitation and adaptation
Odor
Ca2+-CAM binds to the CNG channel, reducing its affinity for ____
The extrusion of Ca2+ through the activation of Na2+/Ca2+ exchange ____
cAMP
Proteins
Individual odor receptors expressing the same gene are dispersed throughout the olfactory epithelium but the axons of the receptors converge on 1 or 2 _____ in the olfactory bulb
Glomeruli
- 1 receptor = ____ molecular feature
- 1 receptor = multiple ___ sharing the same molecular feature
- all receptors encoding the same molecular features = 1 __
- 1 ___ activates several glomeruli
- different odors activates several patterns of ____
- distinct patterns of glomeruli carry distinct odor information to the ____
1
Odors
Glomeruli
Odor
Glomeruli
Cortex
In the olfactory bulb-_____- these contain the 1s order neuron axons which carry information about one particular component of scents
Separate components of an ____ are separated into different glomeruli
These neurons then synapse on ______-> refines the smell sense and relays it to the bran for further processing
Info goes from olfactory bulb to _____ route and _____ route
Glomeruli
Odour
Mitral cells
Subcortical
Thalamo-cortical
______ route to regions of lambic system-medial sides of temporal lobe (primary olfactory cortex)
_____ route for conscious perception of smell and fine discrimination of smell
Subcortical
Thalamo -cortical
Olfaction at cortical neurons follow “_______”
Populating coding
________- accessory olfactory bulb pathways (pheromone detection)
Vomeronasal organ
There is evidence in animals that the _____ via, major histocompatibility (MHC) molecules, can leave a distinct ___ in urine that can be detected by mice
Mice will more likely mate with ____ mice rather than ___ mice if confronted with multiple mates . This is a means to prevent he defects associated with ____
Immune system
Odor
Distantly relates, closely related
In-breeding
