Cellular mechanisms and cognition Flashcards
G.W., a college-aged female who developed symptoms
of paranoia,
D…………………………………..
thinking, and emotional behavior was later diagnosed
with
S………………………….
Disorderly
Schizophrenia
Schizophrenia affects some 1% of the population and is
considered to be a disorder of
C……………………………
that has both genetic and
E……………………………
etiologies.
Cognition
Environmental
Neurons and
G……………………
cells make up the nervous system.
Glial
Neurons are the cells that
T…………………………..
information throughout the nervous system. Most
neurons consist of a cell soma (body),
A……………………,
and
D……………………………………
Transmit
Axon
Dendrites
Neurons come in many shapes and sizes, but they can
be classified into four morphological types:
U……………………,
B…………………,
P……………………………….
and
M………………………….
Unipolar
Bipolar
Pseudounipolar
Multipolar
Synapses occur at various
L……………………………………
along the neuron, primarily at the dendrites, and often on
the dendritic
S…………………,
where information is
R……………………..
Locations
Spines
Received
The presynaptic cell is located
B…………………….
the synapse with respect to information flow; the
P…………………………
cell is located after the synapse with respect to
information flow. Nearly all neurons are both pre-and
postsynaptic, since they both
R…………………….
and
T……………………… information.
Before
Postsynaptic
Receive
Transmit
Glial cells aid in the speed of information transfer by
forming M……………………
around the axons of the neurons; they also carry out other
roles in the nervous system, such as providing structural
support and forming the
B……………..-B……………………. B…………………………..
Myeling
Blood-Brain Barrier
An A………………………………..
is a type of glial cell that forms the blood-brain barrier.
Astrocyte
An oligodendrocyte is a type of glial cell that forms myelin
in the C………………….. N…………………………. S……………………….
Central Nervous System.
A S…………………… cell is a type of glial cell that forms
myelin in the peripheral nervous system.
Schwann
Nodes of Ranvier are the spaces between
S…………………………
of myelin where voltage-gated Na⁺ and K⁺ channels are
located and action potentials occur.
Sheaths
The resting membrane potential is the difference in the
V……………………………..
across the neuronal membrane during rest (i.e., not
during any phase of the action potential).
Voltage
The permeability of a membrane for a specific ion
depends on the extent to which the ion
C……………………
permits ions to cross the
M…………………………..
Channel
Membrane
ATP is the main source of
E………………………….
for the neuron and is used to operate the
Na⁺-……… pump.
Energy
K⁺
The electrical gradient results from the
A…………………………………..
distribution of ions across the membrane.
The electrical difference across the membrane is the
basis of the
R…………………….. potential.
Asymmetrical
Resting
The Nernst equation is used to find the equilibrium
potential for the
I……….
Ion
The G………………….. equation
takes into account the
P………………………………..
of several ions in determining the membrane potential.
Goldman
Permeability
Passive current conduction is called electronic
conduction or
D…………………………….. conduction.
Decremental
A depolarizing current makes the inside of the cell
M…………………. P…………………….
and therefore more likely to generate an action potential.
More Positive
A H…………………………………….
current makes the inside of the cell less positive and
therefore less likely an action potential.
Hyperpolarizing
The spike-triggering zone is the part of the neuron where
the A………………… P……………………
is generated.
Action Potential
Action potentials are an all-or-none phenomenon:
The amplitude of the action potential does
N…….. D……………….
on the S……………..
of the triggering depolarization, as long as that
depolarization reaches threshold for initiating the
A……………….. P……………………..
Not Depend
Size
Action Potential
Voltage-gated C…………………….
are of prime importance of generating an action potential
because they open and close according to the
M…………………………… P……………………………
Channels
Membrane Potential
The large depolarization that is characteristics of the
I……………………….. phase
of the action potential is driven by the self-reinforcing
cycle of the voltage-gated
N… channels.
Initial
Na⁺
K⁺ channels open
more S……………………….
than Na⁺ channels, but K⁺ efflux out of the cell is
much G…………………
than Na⁺ influx into the cell.
Slowly
Greater
After the Na⁺ have closed, some K⁺ channels will remain
O………………….,
bringing the membrane potential closer to the K⁺
equilibrium potential, which is below the resting potential
of the M…………………………..
Open
Membrane
The I………………………………..
of the Na⁺ channels leads to the absolute
R……………………………. period,
during which no action potentials can be generated.
Inactivation
Refractory
During the R……………………..
refractory period, which follows
the A………………………
refractory period, the membrane is hyperpolarized
because of the
S…………… closure
of K⁺ channels. During this time it is more difficult, but not
impossible, for an action potential
to be G…………………………
Relative
Absolute
Slow
Generated
M……………………
allows for the rapid transmission of an action potential
down an axon via saltatory conduction.
Myelin
Ion channels are formed by
T………………………………………..
proteins that create passageways through which ions
can flow.
Transmembrane
The P…………………………
that make up ion have several levels of structure:
primary (order of the A…………………… A………………….),
secondary (how the amino acid chains coil, as in a
A………………- H…………………), tertiary (folding of coiled
amino acids upon themselves to C……………….
complex three-dimensional structures),
quaternary (combining of T………………….. structures to
create a final structure).
Proteins
Amino Acids
Alpha-Helix
Create
Tertiary
