Animal Physiology Final Exam with
correct answers
A stimulating depolarizing current that depolarizes the axon hillock just slightly negative to the
threshold will - ** VERIFIED ANSWERS **✔✔produce a temporary graded potential
Which glial cells function as metabolic intermediaries between capillaries and neurons? - **
VERIFIED ANSWERS **✔✔Astrocytes
In myelinated axons, action potentials occur - ** VERIFIED ANSWERS **✔✔only at the nodes of
Ranvier
Which term best describes the movement of ions across a membrane? - ** VERIFIED ANSWERS
**✔✔Current
Which character of neurons affects conduction velocity the least? - ** VERIFIED ANSWERS
**✔✔axon length
Which of the following actively contributes to the cell's membrane potential? - ** VERIFIED
ANSWERS **✔✔Electrogenic ion pumps
Which statement regarding cardiac pacemaker cells is false - ** VERIFIED ANSWERS **✔✔The
pacemaker cells are modified neural tissue
Neurons that relay sensory signals to integrative centers of the CNS are called - ** VERIFIED
ANSWERS **✔✔afferent neurons
_______ channels govern the generation of an action potential. - ** VERIFIED ANSWERS
**✔✔Voltage-gated Na+
,If a current pulse is generated on the membrane and creates a passive potential, which statement
will be true? - ** VERIFIED ANSWERS **✔✔The change in the membrane potential will decrease
as the distance from the current pulse increases
The neuron converts an electrical signal to a chemical signal in the - ** VERIFIED ANSWERS
**✔✔presynaptic terminal
_______ are responsible for extending the time of the cardiac action potential relative to a neural
action potential. - ** VERIFIED ANSWERS **✔✔Slow Ca2+ channels
In a typical neuron, which ion is in passive equilibrium across the cell membrane? - ** VERIFIED
ANSWERS **✔✔Cl-
A decrease in the absolute value of the membrane potential toward zero is called - ** VERIFIED
ANSWERS **✔✔depolarization
Which statement regarding the action potential is FALSE? - ** VERIFIED ANSWERS **✔✔In an
extremely long axon, the action potential eventually will degrade.
The time constant (τ) depends on the _______ of the membrane. - ** VERIFIED ANSWERS
**✔✔resistance and capacitance
Considering the cycle of an action potential, when is the permeability to K+ at its greatest? - **
VERIFIED ANSWERS **✔✔During the falling phase of the action potential
What allows the action potential to return to a repolarized state? - ** VERIFIED ANSWERS
**✔✔Voltage-gated Na+ channels become inactivated.
If ouabain was used to block Na+-K+-ATPase pumps, - ** VERIFIED ANSWERS **✔✔Na+ would
go to equilibrium across the cell membrane.
, The plasma membrane of a resting neuron is most permeable to which ion? - ** VERIFIED
ANSWERS **✔✔K+
Calmodulin binds to _______ and becomes activated. - ** VERIFIED ANSWERS **✔✔Ca2+
Which protein cannot contact a G protein directly? - ** VERIFIED ANSWERS **✔✔Protein kinase C
Which statement regarding chemical synapses is true? - ** VERIFIED ANSWERS **✔✔Chemical
synapses have high plasticity.
Which statement about the neuromuscular junction acetylcholine (Ach) receptor is false? - **
VERIFIED ANSWERS **✔✔The probability that an ACh channel will open depends on membrane
voltage.
The protein responsible for triggering the actual release of neurotransmitter at the synapse is - **
VERIFIED ANSWERS **✔✔synaptotagmin.
What is the relationship between synaptic facilitation and behavioral sensitization? - ** VERIFIED
ANSWERS **✔✔Synaptic facilitation underlies behavioral sensitization.
The induction of long-term potentiation occurs in the - ** VERIFIED ANSWERS **✔✔postsynaptic
neuron.
Epinephrine is - ** VERIFIED ANSWERS **✔✔either excitatory or inhibitory.
Which substance is most directly responsible for exocytosis of synaptic vesicles? - ** VERIFIED
ANSWERS **✔✔Ca2+
What is the mechanistic explanation for sensitization? - ** VERIFIED ANSWERS **✔✔Increase in
calcium flux
correct answers
A stimulating depolarizing current that depolarizes the axon hillock just slightly negative to the
threshold will - ** VERIFIED ANSWERS **✔✔produce a temporary graded potential
Which glial cells function as metabolic intermediaries between capillaries and neurons? - **
VERIFIED ANSWERS **✔✔Astrocytes
In myelinated axons, action potentials occur - ** VERIFIED ANSWERS **✔✔only at the nodes of
Ranvier
Which term best describes the movement of ions across a membrane? - ** VERIFIED ANSWERS
**✔✔Current
Which character of neurons affects conduction velocity the least? - ** VERIFIED ANSWERS
**✔✔axon length
Which of the following actively contributes to the cell's membrane potential? - ** VERIFIED
ANSWERS **✔✔Electrogenic ion pumps
Which statement regarding cardiac pacemaker cells is false - ** VERIFIED ANSWERS **✔✔The
pacemaker cells are modified neural tissue
Neurons that relay sensory signals to integrative centers of the CNS are called - ** VERIFIED
ANSWERS **✔✔afferent neurons
_______ channels govern the generation of an action potential. - ** VERIFIED ANSWERS
**✔✔Voltage-gated Na+
,If a current pulse is generated on the membrane and creates a passive potential, which statement
will be true? - ** VERIFIED ANSWERS **✔✔The change in the membrane potential will decrease
as the distance from the current pulse increases
The neuron converts an electrical signal to a chemical signal in the - ** VERIFIED ANSWERS
**✔✔presynaptic terminal
_______ are responsible for extending the time of the cardiac action potential relative to a neural
action potential. - ** VERIFIED ANSWERS **✔✔Slow Ca2+ channels
In a typical neuron, which ion is in passive equilibrium across the cell membrane? - ** VERIFIED
ANSWERS **✔✔Cl-
A decrease in the absolute value of the membrane potential toward zero is called - ** VERIFIED
ANSWERS **✔✔depolarization
Which statement regarding the action potential is FALSE? - ** VERIFIED ANSWERS **✔✔In an
extremely long axon, the action potential eventually will degrade.
The time constant (τ) depends on the _______ of the membrane. - ** VERIFIED ANSWERS
**✔✔resistance and capacitance
Considering the cycle of an action potential, when is the permeability to K+ at its greatest? - **
VERIFIED ANSWERS **✔✔During the falling phase of the action potential
What allows the action potential to return to a repolarized state? - ** VERIFIED ANSWERS
**✔✔Voltage-gated Na+ channels become inactivated.
If ouabain was used to block Na+-K+-ATPase pumps, - ** VERIFIED ANSWERS **✔✔Na+ would
go to equilibrium across the cell membrane.
, The plasma membrane of a resting neuron is most permeable to which ion? - ** VERIFIED
ANSWERS **✔✔K+
Calmodulin binds to _______ and becomes activated. - ** VERIFIED ANSWERS **✔✔Ca2+
Which protein cannot contact a G protein directly? - ** VERIFIED ANSWERS **✔✔Protein kinase C
Which statement regarding chemical synapses is true? - ** VERIFIED ANSWERS **✔✔Chemical
synapses have high plasticity.
Which statement about the neuromuscular junction acetylcholine (Ach) receptor is false? - **
VERIFIED ANSWERS **✔✔The probability that an ACh channel will open depends on membrane
voltage.
The protein responsible for triggering the actual release of neurotransmitter at the synapse is - **
VERIFIED ANSWERS **✔✔synaptotagmin.
What is the relationship between synaptic facilitation and behavioral sensitization? - ** VERIFIED
ANSWERS **✔✔Synaptic facilitation underlies behavioral sensitization.
The induction of long-term potentiation occurs in the - ** VERIFIED ANSWERS **✔✔postsynaptic
neuron.
Epinephrine is - ** VERIFIED ANSWERS **✔✔either excitatory or inhibitory.
Which substance is most directly responsible for exocytosis of synaptic vesicles? - ** VERIFIED
ANSWERS **✔✔Ca2+
What is the mechanistic explanation for sensitization? - ** VERIFIED ANSWERS **✔✔Increase in
calcium flux
