MCAT Human Anatomy and Physiology
Study Exam Questions with 100%
Correct Answers.
action potential - CORRECT ANSWER The generation of a moving electrochemical impulse
unidirectionally down an axon
synaptic transmission - CORRECT ANSWER The electrical or chemical signal an action potential transmits
to a neuron or effector when it reaches the axon terminal
neuron - CORRECT ANSWER The functional and structural unit of the nervous system
soma - CORRECT ANSWER Central cell body of a neuron
dendrite - CORRECT ANSWER The receiving projections of a neuron
bioplar neuron - CORRECT ANSWER A neuron with only one dendrite
multipolar neuron - CORRECT ANSWER A neuron with multiple dendrites
synaptic knob - CORRECT ANSWER The branching end points of the axon, where they connect with
other cells
synaptic cleft - CORRECT ANSWER The gap between an axon terminal and the recieving cell
resting membrane potential - CORRECT ANSWER Generally around -70 mV, this is the negative potential
of a neuron due to the activity of the sodium-potassium ATPase pumping 3 sodiums out and 2
potassium in.
,leak channels - CORRECT ANSWER Ion channels which are always open to allow ions to leak down their
gradient
voltage-gated sodium channels - CORRECT ANSWER Open in response to decreasing polarization,
allowing sodium to enter the cell
threshold potential - CORRECT ANSWER About -50 mV, the electric potential needed to open most
voltage-gated sodium channels
repolarization - CORRECT ANSWER A return to the resting membrane potential from the peak voltage
potential generated during the action potential
myelin - CORRECT ANSWER An insulating layer of cells that protects the axon and increases the speed of
the action potential by saltatory conduction
Schwann cells - CORRECT ANSWER Glial cells found in the peripheral nervous system which insulate
neurons and increase the speed of conduction
node of Ranvier - CORRECT ANSWER Areas where ion channels are located on a myelinated neuron, the
action potential jumps between these, which increases propagation speed
glial cells - CORRECT ANSWER Cells which provide structure and support for neurons
oligodendrocytes - CORRECT ANSWER A glial cell which forms a myelin sheath in the central nervous
system
equilibrium potential - CORRECT ANSWER The membrane potential where the net movement of ions
does not occur
Nernst equation - CORRECT ANSWER E = (RT/zF)ln([outside]/[inside])
,refractory period - CORRECT ANSWER The time period when an action potential has just occurred, and
another one cannot be generated
absolute refractory period - CORRECT ANSWER Time where a neuron cannot fire at all, regardless of the
depolarization
relative refractory period - CORRECT ANSWER Time where a neuron requires a much greater
depolarization to generate an action potential
hyperpolarization - CORRECT ANSWER More negative voltage of a neuron
electrical synapse - CORRECT ANSWER The point where two neurons are joined by gap junctions, and
the depolarization can pass directly from one cell to the other
chemical synapse - CORRECT ANSWER A synapse where neurotransmitter is released, and the electrical
signal is converted to a chemical signal
GABA - CORRECT ANSWER Gamma-aminobutyric acid, an inhibitory neurotransmitter in the central
nervous system
serotonin - CORRECT ANSWER A common neutrotransmitter in the central nervous system which has
functions in appetite, sexuality, sleep, and mood
dopamine - CORRECT ANSWER A neurotransmitter commonly known as the "reward molecule"
norepinephrine - CORRECT ANSWER An excititory neurotransmitter which is central to the sympathetic
nervous response
excititory - CORRECT ANSWER A term for a neurotransmitter that depolarizes the postsynaptic neuron
inhibitory - CORRECT ANSWER A term for a neurotransmitter that hyperpolarizes the postsynaptic
neuron
, all-or-nothing - CORRECT ANSWER Describes the tendency of a neuron to either fully fire an action
potential, or not fire at all, depending on if a specific threshold is reached
summation - CORRECT ANSWER The addition of inhibitory and excititory neuron potentials in
determining if an action potential is fired
temporal summation - CORRECT ANSWER Decides if an action potential is fired based on how rapidly
EPSPs or IPSPs are received
spatial summation - CORRECT ANSWER Decides if an action potential is fired based on if excititory
potentials are close enough together to fully depolarize a section of membrane, leading to the full action
potential
sensory functions - CORRECT ANSWER Functions of the nervous system carried out by the peripheral
nervous system, which involves reception of information
integrative functions - CORRECT ANSWER Functions carried out by the central nervous system which
involve processing of received signals
motor functions - CORRECT ANSWER Functions carried out by the peripheral nervous system which
involve acting on signals given by the central nervous system
motor neuron - CORRECT ANSWER A neuron that carries a CNS signal to an effector
effector - CORRECT ANSWER A muscle or a gland. These are cells that carry out motor functions
efferent neurons - CORRECT ANSWER Also known as motor neurons, carriers a CNS signal to an effector
afferent neuron - CORRECT ANSWER Also known as a sensory neuron, carries a signal from a sensor to
the CNS
Study Exam Questions with 100%
Correct Answers.
action potential - CORRECT ANSWER The generation of a moving electrochemical impulse
unidirectionally down an axon
synaptic transmission - CORRECT ANSWER The electrical or chemical signal an action potential transmits
to a neuron or effector when it reaches the axon terminal
neuron - CORRECT ANSWER The functional and structural unit of the nervous system
soma - CORRECT ANSWER Central cell body of a neuron
dendrite - CORRECT ANSWER The receiving projections of a neuron
bioplar neuron - CORRECT ANSWER A neuron with only one dendrite
multipolar neuron - CORRECT ANSWER A neuron with multiple dendrites
synaptic knob - CORRECT ANSWER The branching end points of the axon, where they connect with
other cells
synaptic cleft - CORRECT ANSWER The gap between an axon terminal and the recieving cell
resting membrane potential - CORRECT ANSWER Generally around -70 mV, this is the negative potential
of a neuron due to the activity of the sodium-potassium ATPase pumping 3 sodiums out and 2
potassium in.
,leak channels - CORRECT ANSWER Ion channels which are always open to allow ions to leak down their
gradient
voltage-gated sodium channels - CORRECT ANSWER Open in response to decreasing polarization,
allowing sodium to enter the cell
threshold potential - CORRECT ANSWER About -50 mV, the electric potential needed to open most
voltage-gated sodium channels
repolarization - CORRECT ANSWER A return to the resting membrane potential from the peak voltage
potential generated during the action potential
myelin - CORRECT ANSWER An insulating layer of cells that protects the axon and increases the speed of
the action potential by saltatory conduction
Schwann cells - CORRECT ANSWER Glial cells found in the peripheral nervous system which insulate
neurons and increase the speed of conduction
node of Ranvier - CORRECT ANSWER Areas where ion channels are located on a myelinated neuron, the
action potential jumps between these, which increases propagation speed
glial cells - CORRECT ANSWER Cells which provide structure and support for neurons
oligodendrocytes - CORRECT ANSWER A glial cell which forms a myelin sheath in the central nervous
system
equilibrium potential - CORRECT ANSWER The membrane potential where the net movement of ions
does not occur
Nernst equation - CORRECT ANSWER E = (RT/zF)ln([outside]/[inside])
,refractory period - CORRECT ANSWER The time period when an action potential has just occurred, and
another one cannot be generated
absolute refractory period - CORRECT ANSWER Time where a neuron cannot fire at all, regardless of the
depolarization
relative refractory period - CORRECT ANSWER Time where a neuron requires a much greater
depolarization to generate an action potential
hyperpolarization - CORRECT ANSWER More negative voltage of a neuron
electrical synapse - CORRECT ANSWER The point where two neurons are joined by gap junctions, and
the depolarization can pass directly from one cell to the other
chemical synapse - CORRECT ANSWER A synapse where neurotransmitter is released, and the electrical
signal is converted to a chemical signal
GABA - CORRECT ANSWER Gamma-aminobutyric acid, an inhibitory neurotransmitter in the central
nervous system
serotonin - CORRECT ANSWER A common neutrotransmitter in the central nervous system which has
functions in appetite, sexuality, sleep, and mood
dopamine - CORRECT ANSWER A neurotransmitter commonly known as the "reward molecule"
norepinephrine - CORRECT ANSWER An excititory neurotransmitter which is central to the sympathetic
nervous response
excititory - CORRECT ANSWER A term for a neurotransmitter that depolarizes the postsynaptic neuron
inhibitory - CORRECT ANSWER A term for a neurotransmitter that hyperpolarizes the postsynaptic
neuron
, all-or-nothing - CORRECT ANSWER Describes the tendency of a neuron to either fully fire an action
potential, or not fire at all, depending on if a specific threshold is reached
summation - CORRECT ANSWER The addition of inhibitory and excititory neuron potentials in
determining if an action potential is fired
temporal summation - CORRECT ANSWER Decides if an action potential is fired based on how rapidly
EPSPs or IPSPs are received
spatial summation - CORRECT ANSWER Decides if an action potential is fired based on if excititory
potentials are close enough together to fully depolarize a section of membrane, leading to the full action
potential
sensory functions - CORRECT ANSWER Functions of the nervous system carried out by the peripheral
nervous system, which involves reception of information
integrative functions - CORRECT ANSWER Functions carried out by the central nervous system which
involve processing of received signals
motor functions - CORRECT ANSWER Functions carried out by the peripheral nervous system which
involve acting on signals given by the central nervous system
motor neuron - CORRECT ANSWER A neuron that carries a CNS signal to an effector
effector - CORRECT ANSWER A muscle or a gland. These are cells that carry out motor functions
efferent neurons - CORRECT ANSWER Also known as motor neurons, carriers a CNS signal to an effector
afferent neuron - CORRECT ANSWER Also known as a sensory neuron, carries a signal from a sensor to
the CNS
