Transcript Document

Chemical Senses:Gustation
Background
Basic
Complex
Organs
Anatomy
Gustatory
Taste
receptor
Neural
categories
offlavors
of
taste
Transduction
the
Pathway
cells
tongue
1.
Mechanism
Each
by
activates
which
different
detectcombination
chemicals
3.
Taste food
stimuli
may: weacan
Circuit
Bitter
Types
Basic
process
of
basic
tastes
in
both
the
internal
and
external
environment
a.
Pass
directly
through
an
ion
channel
(salt
2.
System
I
Salt
3.
Chemical
receptors
in
the
arteries
in
the
Gustation
3.
Papillae
and
Olfaction
have
similar
tasks
1.
Tongue
Sour
NT
release
from
taste
cells
causes
an
AP in
3.
G-protein
Chemicals
activates
in
the
environment
an
effector
that
enzymeare
1.Chemoreceptors
in
skin
and
mucous
1.
When
taste
receptor
is
activated
by
the
4.
Systems
are
separate
and
different
and
2.Most
2.
Taste
foods
and
olfaction
have
distinctive
are
the
most
flavor
familiar
as
a
and
a.
Bitter
sour)
tastants
can
directly
block
a
K+
1.
Na+
flows
down
a
concentration
gradient
3.
Information
is
relayed
to
the
thalamus
3.
System
II
neck
measure
CO2
&
O2
levels
in
the
blood
1.
Basic
tastes
1.
Salty
2.
Taste
distribution
1.
a.
Detection
Small
projections
of
environmental
chemicals
a.
Primary
organ
Sweetness
1.
Foods
that
are
sour
have
high
acidity
the
gustatory
afferent
axon
3.
adenylate
deleterious
H+Not
also
cyclase
blocks
often
have
a(cAMP
K+
channel
asmell
bitter
produced)
flavor
membranes
warn
us
about
irritating
chemicals
appropriate
neurons
chemical,
its
membrane
potential
only
merge
at
higher
levels
of
cortical
function
result
chemical
of
their
senses
taste
and
occurring
b.
channel
Bind
to
(same
and
block
transduction
ion
channels
mechanisms
(sour
and
as
into
taste
receptor
cell
(most
salts
are
Na+
(VPM--ventral
posterior
medial
nucleus)
a.
Bitter
tastant
binds
bitter
receptor
4.
Sensory
endings
in
the
muscles
a.
Bitter
across
2.
the
Sour
back
a.
Most
of
the
tongue
is
receptive
to
2.
b.
Both
Each
are
papillae
required
has
to
one
perceive
to
several
flavor
2.
Pharynx,
palate
and
epiglottis
have
some
1.
Molecules
that
are
sweet
bind
to
specific
a.
Acids
(HCl)
when
dissolved
inendings
water
Three
cranial
nerves
(VII,
IX
and
X)
4.
Net
cAMP
Senses
movement
causes
have
evolved
a
of
K+
+
channel
into
primarily
the
cell
to
be
to
depolarizes
blocked
protect
2.
Nerve
endings
in
the
digestive
organs
changes
a.
Form
synapses
with
the
a.
Have
different
chemoreceptors
simultaneously
3.
Many
types
of chemically
sensitive
cells
bitter)
acids)
salts--NaCl)
4.
Information
then
goes
to
the
primary
b.
G-protein
activates
an
effector
enzymerespond
to
acidity
b.
Sour
on
side
3.
closest
Sweet
to
the
back
all
basic
tastes
3.
hundred
Both
have
taste
strong
buds
and
direct
connections
sensitivity
receptor
sites
and
activate
a
cascade
of
2nd
generate
H+
ions
innervate
taste
buds
&
carry
taste
information
the
5.
and
Cell
taste
preserve
depolarizes
cell
(opens
a
Ca++
channel
and
detect
many
types
of
ingested
substances
a.
Receptor
of
gustatory
potential
afferent
axons
near
the
b.
Use
different
transduction
pathways
3.
Other
sensory
modalities
may
contribute
to
a.
Chemoreceptors
c.
b.
Bind
Cell
depolarizes
to
and
open
ion
channels
(some
sweet
2.
Na+
increase
within
the
cell
depolarizes
gustatory
cortex
(parietal
lobe)
phospholipase
C
a.
Burning
sensation
experienced
during
c.
Salty
on
side
more
rostral
than
sour
4.
Bitter
i.
Regions
are
most
sensitive
to
a
to
4.
our
Each
most
taste
basic
bud
needs
has
50-150
taste
cells
3.
Nasal
passages
are
located
so
that
odors
messengers
in
certain
taste
cells
2.
H+
ions
pass
through
the
same
channel
from
tongue,
palate,
epiglottis
&
esophagus
causes
6.
b.
Ca++
Ability
NT
channel
to
release)
detect
opens
bitter
and
has
Ca++
two
separate
in
a.
Viral
agents
may
release
chemicals
into
2.
Depolarizing
bottom
of
the
receptor
taste
bud
potential
cause
Ca++
c.
Have
separate
connections
to
the
brain
a
i.membrane
unique
Distributed
food-tasting
throughout
experience
the
body
amino
c.
Ca++
acids)
channel
is
opened
and
Ca++
in
and
opens
a
voltage
dependent
is
released
from
intracellular
storage
anaerobic
exercise
results
from
lactic
acid
d.
Sweet
across
front
given
taste
a.
5.
Thirst,
Taste
hunger,
cells
are
emotion,
only
1%
sex,
of
the
and
tongue
certain
can
enter
through
the
nose
or
pharynx
and
2.
Molecules
bind
receptor
that
Na+
does
(how
do
we
discriminate
a.
Efferent
target
of
this information
is (some
7.
mechanisms
NT
released
the
GI
tract
that
cause
discomfort,
activate
to
enter
the
cytoplasm
d.
Have
different
effects
on
behavior
a.
Texture,
temperature,
pain
sensitivity
ii.
Report
subconsciously
and
consciously
Bind
to
membrane
receptors
that
activate
NT
released
Ca++
channel
d.
Ca++
increase
causes
NT
release
formation
forms
epithelium
of
memory
contribute
to
the
perception
of
flavor
between
salt
and
sour
then?)
gustatory
nucleus
in
the
medulla
i.
May
result
from
this
evolutionary
pressure
vomiting
reflexes,
etc.
a.
Triggers
the
release
of
NT
hot
and
spicy
flavors
are
actually
a
about
our
internal
state
2nd
messenger
systems
in turnpain
open
3. Ca++
increase
causesthat
the release
of NTor
response)
close ion channels (sweet and bitter)
Exit
BASIM ZWAIN LECTURE NOTES
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