PSB 2000 - Intro to Brain & Behavior Exam 1 | UPDATED
Questions with 100% Verified Answers
Q1: action potential
A: A change in the membrane potential that produces a nerve impulse. All-or-none
response; it doesn't fire "part way," and generally must reach -55mV to produce a
response.
Q2: Do the length and amplitude of an action potential change?
A: No, the length and amplitude of an action potential do not change, but an increase in
stimulus strength causes an increase in the frequency.
Q3: refractory period
A: the time following an action potential during which a new action potential cannot be
initiated
Q4: relative refractory period
A: A period after firing when a neuron is returning to its normal polarized state and will fire
again only if the incoming message is much stronger than usual
Q5: absolute refractory period
A: the period immediately following the firing of a nerve fiber when it cannot be stimulated
no matter how great a stimulus is applied
Q6: ionic diffusion
A: the force on molecules to move from areas of high concentration to areas of low
concentration.
Q7: Depolarization
A: The process during the action potential when sodium is rushing into the cell causing the
interior to become more positive.
Q8: Hyperpolarization
A: The movement of the membrane potential of a cell away from resting potential in a more
negative direction.
Q9: ionotropic receptors
A: receptors that are coupled to ion channels and affect the neuron by causing those
channels to open; associated with ligand-gated channels
Q10: metabotropic receptors
, A: receptors that act through a second messenger system; associated with signal proteins
and G-proteins
Q11: Structure of a neuron
A: soma, dendrites, axon, axon terminals
Q12: synaptic cleft
A: The narrow gap that separates the presynaptic neuron from the postsynaptic cell.
Q13: presynaptic neuron
A: conducts impulses toward the synapse
Q14: postsynaptic cell
A: The neuron, muscle, or gland cell that receives the signal from a neuron.
Q15: membrane potential
A: the voltage difference across a membrane
Q16: resting membrane potential
A: the electrical charge of a neuron when it is not active; -70 mV
Q17: sodium-potassium pump
A: a carrier protein that uses ATP to actively transport sodium ions out of a cell and
potassium ions into the cell
Q18: voltage gated channels
A: open and close in response to changes in membrane potential
Q19: sodium channels
A: during depolarization, ____ open
Q20: calcium channels
A: allows neurotransmitters to be released
Q21: ionic influx
A: rushing of ions into a cell
Q22: ionic efflux
A: rushing of ions out of a cell
Questions with 100% Verified Answers
Q1: action potential
A: A change in the membrane potential that produces a nerve impulse. All-or-none
response; it doesn't fire "part way," and generally must reach -55mV to produce a
response.
Q2: Do the length and amplitude of an action potential change?
A: No, the length and amplitude of an action potential do not change, but an increase in
stimulus strength causes an increase in the frequency.
Q3: refractory period
A: the time following an action potential during which a new action potential cannot be
initiated
Q4: relative refractory period
A: A period after firing when a neuron is returning to its normal polarized state and will fire
again only if the incoming message is much stronger than usual
Q5: absolute refractory period
A: the period immediately following the firing of a nerve fiber when it cannot be stimulated
no matter how great a stimulus is applied
Q6: ionic diffusion
A: the force on molecules to move from areas of high concentration to areas of low
concentration.
Q7: Depolarization
A: The process during the action potential when sodium is rushing into the cell causing the
interior to become more positive.
Q8: Hyperpolarization
A: The movement of the membrane potential of a cell away from resting potential in a more
negative direction.
Q9: ionotropic receptors
A: receptors that are coupled to ion channels and affect the neuron by causing those
channels to open; associated with ligand-gated channels
Q10: metabotropic receptors
, A: receptors that act through a second messenger system; associated with signal proteins
and G-proteins
Q11: Structure of a neuron
A: soma, dendrites, axon, axon terminals
Q12: synaptic cleft
A: The narrow gap that separates the presynaptic neuron from the postsynaptic cell.
Q13: presynaptic neuron
A: conducts impulses toward the synapse
Q14: postsynaptic cell
A: The neuron, muscle, or gland cell that receives the signal from a neuron.
Q15: membrane potential
A: the voltage difference across a membrane
Q16: resting membrane potential
A: the electrical charge of a neuron when it is not active; -70 mV
Q17: sodium-potassium pump
A: a carrier protein that uses ATP to actively transport sodium ions out of a cell and
potassium ions into the cell
Q18: voltage gated channels
A: open and close in response to changes in membrane potential
Q19: sodium channels
A: during depolarization, ____ open
Q20: calcium channels
A: allows neurotransmitters to be released
Q21: ionic influx
A: rushing of ions into a cell
Q22: ionic efflux
A: rushing of ions out of a cell
