PNB EXAM 3: CHAPTERS 9 – 11 with
complete solutions passed
Characteristics of Neurons - ANS ✔✔high metabolic rate (high demand of ATP to maintain ion
concentrations), extreme longevity, non-mitotic (terminally differentiated)
Neuronal Structures - ANS ✔✔Dendrites, Cell Body, Axon, Axon Terminal
Multipolar Neurons - ANS ✔✔have many dendrites and a single axon
Dendrites - ANS ✔✔the branched part of a neuron that receives many impulses simultaneously
using receptors.
Soma - ANS ✔✔neuron cell body, contains organelles (many mitochondria & ribosomes)
Axon - ANS ✔✔the extension of a neuron, ending in branching terminal fibers, through which
messages pass to other neurons or to muscles or glands
axon hillock - ANS ✔✔region where the axon connects to the cell body
Axon terminal - ANS ✔✔distal part of the axon, forms a synapse (connection) with another cell
(postsynaptic cell)
axo-dendritic synapse - ANS ✔✔axon terminal synapses on a dendrite
,Passive Electrical Signals - ANS ✔✔a transient change in membrane potential that dissipates as
it propagates in space and time. Its specific to one region of the cell and for a very short period
of time. ex. Gradient/synaptic potentials
Active Electrical Signals - ANS ✔✔a change in membrane potential that is maintained over a
long distance. Ex. Action potential
Area of Neuron for Signal Input - ANS ✔✔Dendrite
Area of Neuron for Signal Integration - ANS ✔✔Soma
Area of Neuron for Generation of Action Potential - ANS ✔✔Axon Hillock
Area of Neuron where Action Potential Propagates - ANS ✔✔Axon
Area of Neuron for Signal Output (Chemical) - ANS ✔✔Synapse of the Axon Terminal
Axon Terminal - ANS ✔✔The endpoint of a neuron where neurotransmitters are stored
Synapse - ANS ✔✔Gap between the axon tip of the sending neuron and the dendrite or cell
body of the receiving cell
Synapse potentials - ANS ✔✔Passive and primarily by ligand gated ion channels.
potential difference across the postsynaptic membrane that results from the action of
neurotransmitters at a neuronal synapse. In other words, it is the "incoming" signal that a
neuron receives
, EPSP - ANS ✔✔Excitatory postsynaptic potential; a slight depolarization of a postsynaptic cell,
bringing the membrane potential of that cell closer to the threshold for an action potential.
Graded & decremental
IPSP - ANS ✔✔Inhibitory postsynaptic potential; a slight hyperpolarization of the postsynaptic
cell, moving the membrane potential of that cell further from threshold. Graded & decremental
Graded Potential - ANS ✔✔decrease in strength as they spread out in all directions from the
point of origin.
Integration of synaptic potential - ANS ✔✔Soma receives many EPSPs and IPSPs at once and
must try to make sense of these signals
Post Synaptic Potential Summation - ANS ✔✔Spatial or temporal, if the neuron is able to
produce enough depolarization the action potential is produced.
Action Potential - ANS ✔✔Active electrical current, a burst of electrical activity that rapidly
propagates through the cell.
Origin of Action Potential in Neuron - ANS ✔✔Axon Hillock, highest density of voltage gated Na
channels
Phases of action potential - ANS ✔✔1- Resting membrane potential
2- depolarizing stimulus
3- membrane depolarizes to threshold. Voltage gated Na channels activate and Na enters the
cell. Voltage Gated K channels begin to open slowly
4- Rapid Na entry depolarizes the cell
5- Na channels inactivate and slower K channels open
6- K moves from cell to extracellular fluid
complete solutions passed
Characteristics of Neurons - ANS ✔✔high metabolic rate (high demand of ATP to maintain ion
concentrations), extreme longevity, non-mitotic (terminally differentiated)
Neuronal Structures - ANS ✔✔Dendrites, Cell Body, Axon, Axon Terminal
Multipolar Neurons - ANS ✔✔have many dendrites and a single axon
Dendrites - ANS ✔✔the branched part of a neuron that receives many impulses simultaneously
using receptors.
Soma - ANS ✔✔neuron cell body, contains organelles (many mitochondria & ribosomes)
Axon - ANS ✔✔the extension of a neuron, ending in branching terminal fibers, through which
messages pass to other neurons or to muscles or glands
axon hillock - ANS ✔✔region where the axon connects to the cell body
Axon terminal - ANS ✔✔distal part of the axon, forms a synapse (connection) with another cell
(postsynaptic cell)
axo-dendritic synapse - ANS ✔✔axon terminal synapses on a dendrite
,Passive Electrical Signals - ANS ✔✔a transient change in membrane potential that dissipates as
it propagates in space and time. Its specific to one region of the cell and for a very short period
of time. ex. Gradient/synaptic potentials
Active Electrical Signals - ANS ✔✔a change in membrane potential that is maintained over a
long distance. Ex. Action potential
Area of Neuron for Signal Input - ANS ✔✔Dendrite
Area of Neuron for Signal Integration - ANS ✔✔Soma
Area of Neuron for Generation of Action Potential - ANS ✔✔Axon Hillock
Area of Neuron where Action Potential Propagates - ANS ✔✔Axon
Area of Neuron for Signal Output (Chemical) - ANS ✔✔Synapse of the Axon Terminal
Axon Terminal - ANS ✔✔The endpoint of a neuron where neurotransmitters are stored
Synapse - ANS ✔✔Gap between the axon tip of the sending neuron and the dendrite or cell
body of the receiving cell
Synapse potentials - ANS ✔✔Passive and primarily by ligand gated ion channels.
potential difference across the postsynaptic membrane that results from the action of
neurotransmitters at a neuronal synapse. In other words, it is the "incoming" signal that a
neuron receives
, EPSP - ANS ✔✔Excitatory postsynaptic potential; a slight depolarization of a postsynaptic cell,
bringing the membrane potential of that cell closer to the threshold for an action potential.
Graded & decremental
IPSP - ANS ✔✔Inhibitory postsynaptic potential; a slight hyperpolarization of the postsynaptic
cell, moving the membrane potential of that cell further from threshold. Graded & decremental
Graded Potential - ANS ✔✔decrease in strength as they spread out in all directions from the
point of origin.
Integration of synaptic potential - ANS ✔✔Soma receives many EPSPs and IPSPs at once and
must try to make sense of these signals
Post Synaptic Potential Summation - ANS ✔✔Spatial or temporal, if the neuron is able to
produce enough depolarization the action potential is produced.
Action Potential - ANS ✔✔Active electrical current, a burst of electrical activity that rapidly
propagates through the cell.
Origin of Action Potential in Neuron - ANS ✔✔Axon Hillock, highest density of voltage gated Na
channels
Phases of action potential - ANS ✔✔1- Resting membrane potential
2- depolarizing stimulus
3- membrane depolarizes to threshold. Voltage gated Na channels activate and Na enters the
cell. Voltage Gated K channels begin to open slowly
4- Rapid Na entry depolarizes the cell
5- Na channels inactivate and slower K channels open
6- K moves from cell to extracellular fluid
