Understanding Patho Quiz 2
Neurological System: Exam 1
Questions and verified answers
What occurs during the generation of an action potential? ✔️✔️Correct Ans-Na+ channels open which
results in a change in membrane potential causing K+ channels to open.
The effect when Na+ channels open is that it becomes self-__________ and self-______________.
✔️✔️Correct Ans-effect becomes self-generating and is urged on by positive feedback (spikes).
depolarization occurs.
self-limiting.
What are the 3 components of the neuron? ✔️✔️Correct Ans-cell body (soma), dendrites, axons
where is the cell body (soma) located? ✔️✔️Correct Ans-mainly in the CNS
Densely packed cell bodies in the CNS are?
PNS? ✔️✔️Correct Ans-nuclei.
ganglia.
What is located in the cell body (soma)? ✔️✔️Correct Ans-nucleus and cytoplasm.
Dendrites are the ________ portion of the neuron. ✔️✔️Correct Ans-Receptive portion.
They accept and sense external stimuli. Stimulate incoming signals to cell body.
,Axons transmit impulses where? ✔️✔️Correct Ans-Transmit impulses AWAY from cell body of
neuron.
the long thread like part of a nerve cell along which impulses are conducted from the cell body to
other cells.
what is the cone-shaped process where the axon leaves the cell body? ✔️✔️Correct Ans-axon hillock
As dendrites bring signals to the axon hillock, what occurs? ✔️✔️Correct Ans-the inhibitory and
exhibitory graded potentials are summed to determine if an action potential can occur to send a signal
down the axon hillock.
What part of the axon has the lowest threshold for stimulation?
and what occurs here? ✔️✔️Correct Ans-The initial segment of the axon.
the action potentials begin at this point.
Describe membrane polarization during a neuron's resting state. ✔️✔️Correct Ans-imbalance of ions is
created and maintained by ion pumps.
The membrane lacks permeability to ions.
unit of measurement of ion concentration ✔️✔️Correct Ans-mM (mOsm)
the separation or ______________ of ions and charges creates _____________. ✔️✔️Correct Ans-
polarization; an electrical potential.
the further distance between the charges = ✔️✔️Correct Ans-the more polarized .
Therefore, the closer the distance between the ends results in: ✔️✔️Correct Ans-depolarization
The membrane potential refers to the _______________ of the cell. ✔️✔️Correct Ans-inside
,If the membrane potential is -70 mV, this means: ✔️✔️Correct Ans-that the inside (cytoplasm) is more
negative than the extracellular environment.
The difference in potential is found where on the cell? ✔️✔️Correct Ans-at the membrane.
NOT the cell as a whole.
what ions cause the difference in potential found at the membrane? ✔️✔️Correct Ans-mostly Na+, but
K+ too.
Which way would K+ move if left to diffusion and the membrane where permeable?
Na+? ✔️✔️Correct Ans-Move from high to low concentration. So K+ would move to ECF and Na+ to
the ICF.
If there is 150mM Na+ and 5mM K+ outside the cell and 15mM Na+ and 150mM K+ inside, why
would they not diffuse equally fast across the membrane? ✔️✔️Correct Ans-If fully permeable, many
more Na+ would move into the cell than K+ out d/t negative charge and lower concentration of Na+
inside the cell.
Na+ has an electrical and chemical gradient that is driving Na+ into the ICF.
The positive Na+ will be highly attracted to the negative ICF. Additional force to pull Na+ in and
retain K+.
what is used to describe the forces affecting ion movement if allowed to become permeable to a
membrane? ✔️✔️Correct Ans-electrochemical gradient.
Chemical gradients move from __________ concentration to __________.
This makes them become: ✔️✔️Correct Ans-high concentration to low conentration.
becomes more random -- lower energy state.
, How to electrical gradients operate? ✔️✔️Correct Ans-opposite charges attract, similar charges repel.
This can set up a force to move charged particles.
Potentials are charges that are separated by:
They are measured in: ✔️✔️Correct Ans-a membrane.
volts or millivolts (mV)
Resting membrane potential is the result of: ✔️✔️Correct Ans-retained proteins within the cell and ions
(mostly Na+ and K+) creating electrochemical gradients.
This results in a relatively negative charge within the inner aspect of the plasma membrane.
Why does K+ not move as freely as Na+ with a fully permeable membrane? ✔️✔️Correct Ans-K+ has
a chemical gradient that favors its outflux into the ECF.
However, an electrical gradient is present inside the cell that favors K+ to remain inside the cell.
What is an equilibrium potential? ✔️✔️Correct Ans-a way to describe the voltage conditions necessary
to counterbalance the chemical gradient forces of a given single ion so that equilibrium is established
for that ion alone.
movement in = movement out.
example: what will it take voltage-wise (membrane potential) to balance out chemical diffusion for
that ion.
compare the equilibrium potentials between K+, Na+, Ca2+ and Cl-. ✔️✔️Correct Ans-Na+ and Ca2+
have positive equilibrium potentials.
K+ and Cl- have negative ones.
Neurological System: Exam 1
Questions and verified answers
What occurs during the generation of an action potential? ✔️✔️Correct Ans-Na+ channels open which
results in a change in membrane potential causing K+ channels to open.
The effect when Na+ channels open is that it becomes self-__________ and self-______________.
✔️✔️Correct Ans-effect becomes self-generating and is urged on by positive feedback (spikes).
depolarization occurs.
self-limiting.
What are the 3 components of the neuron? ✔️✔️Correct Ans-cell body (soma), dendrites, axons
where is the cell body (soma) located? ✔️✔️Correct Ans-mainly in the CNS
Densely packed cell bodies in the CNS are?
PNS? ✔️✔️Correct Ans-nuclei.
ganglia.
What is located in the cell body (soma)? ✔️✔️Correct Ans-nucleus and cytoplasm.
Dendrites are the ________ portion of the neuron. ✔️✔️Correct Ans-Receptive portion.
They accept and sense external stimuli. Stimulate incoming signals to cell body.
,Axons transmit impulses where? ✔️✔️Correct Ans-Transmit impulses AWAY from cell body of
neuron.
the long thread like part of a nerve cell along which impulses are conducted from the cell body to
other cells.
what is the cone-shaped process where the axon leaves the cell body? ✔️✔️Correct Ans-axon hillock
As dendrites bring signals to the axon hillock, what occurs? ✔️✔️Correct Ans-the inhibitory and
exhibitory graded potentials are summed to determine if an action potential can occur to send a signal
down the axon hillock.
What part of the axon has the lowest threshold for stimulation?
and what occurs here? ✔️✔️Correct Ans-The initial segment of the axon.
the action potentials begin at this point.
Describe membrane polarization during a neuron's resting state. ✔️✔️Correct Ans-imbalance of ions is
created and maintained by ion pumps.
The membrane lacks permeability to ions.
unit of measurement of ion concentration ✔️✔️Correct Ans-mM (mOsm)
the separation or ______________ of ions and charges creates _____________. ✔️✔️Correct Ans-
polarization; an electrical potential.
the further distance between the charges = ✔️✔️Correct Ans-the more polarized .
Therefore, the closer the distance between the ends results in: ✔️✔️Correct Ans-depolarization
The membrane potential refers to the _______________ of the cell. ✔️✔️Correct Ans-inside
,If the membrane potential is -70 mV, this means: ✔️✔️Correct Ans-that the inside (cytoplasm) is more
negative than the extracellular environment.
The difference in potential is found where on the cell? ✔️✔️Correct Ans-at the membrane.
NOT the cell as a whole.
what ions cause the difference in potential found at the membrane? ✔️✔️Correct Ans-mostly Na+, but
K+ too.
Which way would K+ move if left to diffusion and the membrane where permeable?
Na+? ✔️✔️Correct Ans-Move from high to low concentration. So K+ would move to ECF and Na+ to
the ICF.
If there is 150mM Na+ and 5mM K+ outside the cell and 15mM Na+ and 150mM K+ inside, why
would they not diffuse equally fast across the membrane? ✔️✔️Correct Ans-If fully permeable, many
more Na+ would move into the cell than K+ out d/t negative charge and lower concentration of Na+
inside the cell.
Na+ has an electrical and chemical gradient that is driving Na+ into the ICF.
The positive Na+ will be highly attracted to the negative ICF. Additional force to pull Na+ in and
retain K+.
what is used to describe the forces affecting ion movement if allowed to become permeable to a
membrane? ✔️✔️Correct Ans-electrochemical gradient.
Chemical gradients move from __________ concentration to __________.
This makes them become: ✔️✔️Correct Ans-high concentration to low conentration.
becomes more random -- lower energy state.
, How to electrical gradients operate? ✔️✔️Correct Ans-opposite charges attract, similar charges repel.
This can set up a force to move charged particles.
Potentials are charges that are separated by:
They are measured in: ✔️✔️Correct Ans-a membrane.
volts or millivolts (mV)
Resting membrane potential is the result of: ✔️✔️Correct Ans-retained proteins within the cell and ions
(mostly Na+ and K+) creating electrochemical gradients.
This results in a relatively negative charge within the inner aspect of the plasma membrane.
Why does K+ not move as freely as Na+ with a fully permeable membrane? ✔️✔️Correct Ans-K+ has
a chemical gradient that favors its outflux into the ECF.
However, an electrical gradient is present inside the cell that favors K+ to remain inside the cell.
What is an equilibrium potential? ✔️✔️Correct Ans-a way to describe the voltage conditions necessary
to counterbalance the chemical gradient forces of a given single ion so that equilibrium is established
for that ion alone.
movement in = movement out.
example: what will it take voltage-wise (membrane potential) to balance out chemical diffusion for
that ion.
compare the equilibrium potentials between K+, Na+, Ca2+ and Cl-. ✔️✔️Correct Ans-Na+ and Ca2+
have positive equilibrium potentials.
K+ and Cl- have negative ones.
