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Nervous Tissue
BI 121
Each of the following is a function of the nervous system, except
A. providing sensation of the internal and external environments.
B. integrating sensory information.
C. coordinating voluntary and involuntary activities.
D. directing activities that continue for extended periods, such as growth and pregnancy.
E. regulating or controlling peripheral structures and systems.
ANSWER
Each of the following is a function of the nervous system, except
A. providing sensation of the internal and external environments.
B. integrating sensory information.
C. coordinating voluntary and involuntary activities.
D. directing activities that continue for extended periods, such as growth and pregnancy.
E. regulating or controlling peripheral structures and systems.
The function of the astrocytes in the CNS includes which of the following?
A. controlling the interstitial environment
B. guiding neuron development
C. maintaining the blood–brain barrier
D. repairing damaged neural tissue
E. all of the above
ANSWER
The function of the astrocytes in the CNS includes which of the following?
A. controlling the interstitial environment
B. guiding neuron development
C. maintaining the blood–brain barrier
D. repairing damaged neural tissue
E. all of the above
The largest and most numerous neuroglia in the CNS are the
A. astrocytes.
B. ependymal cells.
C. microglia.
D. oligodendrocytes.
E. none of the above
ANSWER
The largest and most numerous neuroglia in the CNS are the
A. astrocytes.
B. ependymal cells.
C. microglia.
D. oligodendrocytes.
E. none of the above
The effect that a neurotransmitter has on the postsynaptic membrane depends on
A. the frequency of neurotransmitter release.
B. the nature of the neurotransmitter.
C. the characteristics of the receptors.
D. the quantity of neurotransmitters released.
E. both A and B
ANSWER
The effect that a neurotransmitter has on the postsynaptic membrane depends on
A. the frequency of neurotransmitter release.
B. the nature of the neurotransmitter.
C. the characteristics of the receptors.
D. the quantity of neurotransmitters released.
E. both A and B
Neurons that have one axon and one dendrite are called
A. anaxonic.
B. unipolar.
C. bipolar.
D. tripolar.
E. multipolar.
ANSWER
Neurons that have one axon and one dendrite are called
A. anaxonic.
B. unipolar.
C. bipolar.
D. tripolar.
E. multipolar.
_____ ions leave the cytoplasm rapidly.
A. Sodium
B. Potassium
C. Calcium
D. both A and C
E. none of the above
ANSWER
_____ ions leave the cytoplasm rapidly.
A. Sodium
B. Potassium
C. Calcium
D. both A and C
E. none of the above
Channels that are always open are known as
A. passive channels.
B. active channels.
C. chemically regulated channels.
D. gated channels.
E. both B and D
ANSWER
Channels that are always open are known as
A. passive channels.
B. active channels.
C. chemically regulated channels.
D. gated channels.
E. both B and D
The brain and spinal cord comprise the _____ nervous system.
A. autonomic
B. peripheral
C. central
D. efferent
E. afferent
ANSWER
The brain and spinal cord comprise the _____ nervous system.
A. autonomic
B. peripheral
C. central
D. efferent
E. afferent
Neurons that have several dendrites and a single axon are called
A. anaxonic.
B. unipolar.
C. bipolar.
D. tripolar.
E. multipolar.
ANSWER
Neurons that have several dendrites and a single axon are called
A. anaxonic.
B. unipolar.
C. bipolar.
D. tripolar.
E. multipolar.
_____ open or close in response to specific stimuli.
A. Passive channels
B. Active channels
C. Chemically regulated channels
D. Gated channels
E. B, C and D
ANSWER
_____ open or close in response to specific stimuli.
A. Passive channels
B. Active channels
C. Chemically regulated channels
D. Gated channels
E. B, C and D
_____ channels open or close in response to physical distortion of the membrane surface.
A. Gated
B. Chemically regulated
C. Active
D. Mechanically regulated
E. Passive
ANSWER
_____ channels open or close in response to physical distortion of the membrane surface.
A. Gated
B. Chemically regulated
C. Active
D. Mechanically regulated
E. Passive
Voluntary control of skeletal muscles is provided by the _____ nervous system.
A. sympathetic
B. parasympathetic
C. afferent
D. somatic
E. autonomic
ANSWER
Voluntary control of skeletal muscles is provided by the _____ nervous system.
A. sympathetic
B. parasympathetic
C. afferent
D. somatic
E. autonomic
Sensory information concerning position and
balance and motor information concerning
skeletal muscles travel over _____ fibers.
A. type A
B. type B
C. type C
D. type D
E. type E
ANSWER
Sensory information concerning position and
balance and motor information concerning
skeletal muscles travel over _____ fibers.
A. type A
B. type B
C. type C
D. type D
E. type E
The part of the peripheral nervous system that brings information to the central nervous system is
A. motor.
B. afferent.
C. efferent.
D. autonomic.
E. somatic.
ANSWER
The part of the peripheral nervous system that brings information to the central nervous system is
A. motor.
B. afferent.
C. efferent.
D. autonomic.
E. somatic.
The resistance across the cell membrane is determined by
A. the thickness of the membrane.
B. the amount of lipid in the membrane.
C. the surface area of the membrane.
D. the number and type of channels in the membrane.
E. the number of ions in the structure of the membrane.
ANSWER
The resistance across the cell membrane is determined by
A. the thickness of the membrane.
B. the amount of lipid in the membrane.
C. the surface area of the membrane.
D. the number and type of channels in the membrane.
E. the number of ions in the structure of the membrane.
Which of the following is not a function of the neuroglia?
A. support
B. information processing
C. secretion of cerebrospinal fluid
D. isolation of neurons
E. phagocytosis
ANSWER
Which of the following is not a function of the neuroglia?
A. support
B. information processing
C. secretion of cerebrospinal fluid
D. isolation of neurons
E. phagocytosis
In the peripheral nervous system, Schwann cells
participate in the repair of damaged nerves by
A. producing new axons.
B. regenerating cell bodies for the neurons.
C. forming a cellular tube that can direct the growth of
new axons.
D. clearing away cellular debris.
E. producing more satellite cells that accomplish the
actual repair.
ANSWER
In the peripheral nervous system, Schwann cells
participate in the repair of damaged nerves by
A. producing new axons.
B. regenerating cell bodies for the neurons.
C. forming a cellular tube that can direct the growth
of new axons.
D. clearing away cellular debris.
E. producing more satellite cells that accomplish the
actual repair.
Bundles of axons are called
A. nerves.
B. tracts.
C. centers.
D. nuclei.
E. ganglia.
ANSWER
Bundles of axons are called
A. nerves.
B. tracts.
C. centers.
D. nuclei.
E. ganglia.
Most neurons lack centrioles. This observation explains
A. why neurons grow such long axons.
B. why neurons cannot regenerate.
C. the conducting ability of neurons.
D. the ability of neurons to communicate with each other.
E. the ability of neurons to produce an axoplasmic flow.
ANSWER
Most neurons lack centrioles. This observation explains
A. why neurons grow such long axons.
B. why neurons cannot regenerate.
C. the conducting ability of neurons.
D. the ability of neurons to communicate with each other.
E. the ability of neurons to produce an axoplasmic flow.
Each of the following is a type of neuroglial cell found in the central nervous system, except
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
ANSWER
Each of the following is a type of neuroglial cell found in the central nervous system, except
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
EPSPs (excitatory postsynaptic potentials) occur when
A. more potassium ions than usual leak out of a cell.
B. more calcium ions than usual leak out of a cell.
C. chloride ions enter a cell.
D. sodium channels are opened.
E. hyperpolarizations occur.
ANSWER
EPSPs (excitatory postsynaptic potentials) occur when
A. more potassium ions than usual leak out of a cell.
B. more calcium ions than usual leak out of a cell.
C. chloride ions enter a cell.
D. sodium channels are opened.
E. hyperpolarizations occur.
At the normal resting potential of a typical neuron, its ion exchange pump transports
A. 1 intracellular sodium ion for 2 extracellular potassium ions.
B. 2 intracellular sodium ions for 1 extracellular potassium ion.
C. 3 intracellular sodium ions for 1 extracellular potassium ion.
D. 3 intracellular sodium ions for 2 extracellular potassium ions.
E. 3 extracellular sodium ions for 2 intracellular potassium ions.
ANSWER
At the normal resting potential of a typical neuron, its ion exchange pump transports
A. 1 intracellular sodium ion for 2 extracellular potassium ions.
B. 2 intracellular sodium ions for 1 extracellular potassium ion.
C. 3 intracellular sodium ions for 1 extracellular potassium ion.
D. 3 intracellular sodium ions for 2 extracellular potassium ions.
E. 3 extracellular sodium ions for 2 intracellular potassium ions.
The largest and most numerous of the
neuroglial cells in the central nervous system are the
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
ANSWER
The largest and most numerous of the
neuroglial cells in the central nervous system are the
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
Many medications introduced into the bloodstream cannot directly affect the neurons of the CNS because
A. oligodendrocytes form a continuous myelin sheath around the axons.
B. the lining of the capillaries in the CNS forms a blood–brain barrier.
C. the neurolemma is impermeable to all types of molecules.
D. the ependymal cells restrict the flow of interstitial fluid between the capillaries and the neurons.
E. glial cells (like the astrocytes) form a physical barrier between the blood vessels and the neuron’s membrane.
ANSWER
Many medications introduced into the bloodstream cannot directly affect the neurons of the CNS because
A. oligodendrocytes form a continuous myelin sheath around the axons.
B. the lining of the capillaries in the CNS forms a blood–brain barrier.
C. the neurolemma is impermeable to all types of molecules.
D. the ependymal cells restrict the flow of interstitial fluid between the capillaries and the neurons.
E. glial cells (like the astrocytes) form a physical barrier between the blood vessels and the neuron’s membrane.
IPSPs (inhibitory postsynaptic potentials)
A. result in local depolarizations.
B. result in local hyperpolarizations.
C. increase membrane permeability to sodium
ions.
D. prevent the efflux of potassium ions.
E. prevent the efflux of calcium ions.
ANSWER
IPSPs (inhibitory postsynaptic potentials)
A. result in local depolarizations.
B. result in local hyperpolarizations.
C. increase membrane permeability to sodium
ions.
D. prevent the efflux of potassium ions.
E. prevent the efflux of calcium ions.
Membrane channels that are always open are called _____ channels.
A. active
B. gated
C. passive
D. regulated
E. local
ANSWER
Membrane channels that are always open are called _____ channels.
A. active
B. gated
C. passive
D. regulated
E. local
Damage to large numbers of oligodendrocytes in
the CNS would result in
A. loss of the structural framework of the brain.
B. a breakdown of the blood–brain barrier.
C. inability to produce scar tissue at the site of an injury.
D. decreased production of cerebrospinal fluid.
E. decreased speed of action potential conduction.
ANSWER
Damage to large numbers of oligodendrocytes in
the CNS would result in
A. loss of the structural framework of the brain.
B. a breakdown of the blood–brain barrier.
C. inability to produce scar tissue at the site of an injury.
D. decreased production of cerebrospinal fluid.
E. decreased speed of action potential conduction.
Functions of astrocytes include all of the following, except
A. maintaining the blood–brain barrier.
B. functioning in action potential transmission.
C. guiding neuron development.
D. performing repairs in damaged neural tissue.
E. creating a three-dimensional framework for
the CNS.
ANSWER
Functions of astrocytes include all of the following, except
A. maintaining the blood–brain barrier.
B. functioning in action potential transmission.
C. guiding neuron development.
D. performing repairs in damaged neural tissue.
E. creating a three-dimensional framework for the CNS.
Damage to ependymal cells would affect the
A. formation of myelin sheaths.
B. formation of cerebrospinal fluid.
C. formation of ganglia.
D. repair of axons.
E. transport of neurotransmitters within axons.
ANSWER
Damage to ependymal cells would affect the
A. formation of myelin sheaths.
B. formation of cerebrospinal fluid.
C. formation of ganglia.
D. repair of axons.
E. transport of neurotransmitters within axons.
Changes in transmembrane potentials
A. can open voltage-regulated channels.
B. can only produce a local potential.
C. can only produce an action potential.
D. can open chemically regulated channels.
E. cannot alter the resting membrane potential.
ANSWER
Changes in transmembrane potentials
A. can open voltage-regulated channels.
B. can only produce a local potential.
C. can only produce an action potential.
D. can open chemically regulated channels.
E. cannot alter the resting membrane potential.
Opening of sodium channels in the membrane of a neuron results in
A. depolarization.
B. repolarization.
C. hyperpolarization.
D. increased negative charge inside the
membrane.
E. reestablishing the resting potential.
ANSWER
Opening of sodium channels in the membrane of a neuron results in
A. depolarization.
B. repolarization.
C. hyperpolarization.
D. increased negative charge inside the
membrane.
E. reestablishing the resting potential.
When a second EPSP arrives at a single synapse before the effects of the first have disappeared, what occurs?
A. spatial summation
B. temporal summation
C. inhibition of the impulse
D. hyperpolarization
E. decrease in speed of impulse transmission
ANSWER
When a second EPSP arrives at a single synapse before the effects of the first have disappeared, what occurs?
A. spatial summation
B. temporal summation
C. inhibition of the impulse
D. hyperpolarization
E. decrease in speed of impulse transmission
The myelin sheaths that surround the axons of some of the neurons in the CNS are formed by
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
ANSWER
The myelin sheaths that surround the axons of some of the neurons in the CNS are formed by
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
Graded potentials
A. produce an effect that increases with distance from the point of stimulation.
B. produce an effect that spreads actively across the membrane surface.
C. may involve either depolarization or hyperpolarization.
D. are all-or-none.
E. involve repolarization.
ANSWER
Graded potentials
A. produce an effect that increases with distance from the point of stimulation.
B. produce an effect that spreads actively across the membrane surface.
C. may involve either depolarization or hyperpolarization.
D. are all-or-none.
E. involve repolarization.
Voltage-regulated channels can be found
A. at the motor end plate.
B. on the surface of dendrites.
C. in the membrane that covers axons.
D. on the soma of neurons.
E. along the perikaryon of neurons.
ANSWER
Voltage-regulated channels can be found
A. at the motor end plate.
B. on the surface of dendrites.
C. in the membrane that covers axons.
D. on the soma of neurons.
E. along the perikaryon of neurons.
If the sodium–potassium pumps in the cell membrane fail to function, all of the following occur, except
A. the extracellular concentration of potassium ions will increase.
B. the neuron will lose its ability to regenerate.
C. the membrane will lose its capacity to generate action potentials.
D. the inside of the membrane will have a resting potential that is more positive than normal.
E. the intracellular concentration of sodium ions will increase.
ANSWER
If the sodium–potassium pumps in the cell membrane fail to function, all of the following occur, except
A. the extracellular concentration of potassium ions will increase.
B. the neuron will lose its ability to regenerate.
C. the membrane will lose its capacity to generate action potentials.
D. the inside of the membrane will have a resting potential that is more positive than normal.
E. the intracellular concentration of sodium ions will increase.
The type of neuroglial cell that is found
lining the ventricles and spinal canal are the
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
ANSWER
The type of neuroglial cell that is found
lining the ventricles and spinal canal are the
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
Active neurons need ATP to support all of the following, except
A. the movement of materials to and from the axon via somatic flow.
B. the synthesis and release of neurotransmitter molecules.
C. the movement of materials to and from the soma via axoplasmic flow.
D. the recovery from action potentials.
E. the recycling of neurotransmitter molecules.
ANSWER
Active neurons need ATP to support all of the following, except
A. the movement of materials to and from the axon via somatic flow.
B. the synthesis and release of neurotransmitter molecules.
C. the movement of materials to and from the soma via axoplasmic flow.
D. the recovery from action potentials.
E. the recycling of neurotransmitter molecules.
The following are the main steps in the generation of an action potential.
1. Sodium channels are inactivated.
2. Voltage-regulated potassium channels open and potassium moves out of the cell, initiating repolarization.
3. Sodium channels regain their normal properties.
4. A graded depolarization brings an area of an excitable membrane to threshold.
5. A temporary hyperpolarization occurs.
6. Sodium channel activation occurs.
7. Sodium ions enter the cell and depolarization occurs.
The proper sequence of these events is
A. 4, 6, 7, 3, 2, 5, 1.
B. 4, 6, 7, 1, 2, 3, 5.
C. 6, 7, 4, 1, 2, 3, 5.
D. 2, 4, 6, 7, 1, 3, 5.
E. 4, 2, 5, 6, 7, 3, 1.
The following are the main steps in the generation of an action potential.
1. Sodium channels are inactivated.
2. Voltage-regulated potassium channels open and potassium moves out of the cell, initiating repolarization.
3. Sodium channels regain their normal properties.
4. A graded depolarization brings an area of an excitable membrane to threshold.
5. A temporary hyperpolarization occurs.
6. Sodium channel activation occurs.
7. Sodium ions enter the cell and depolarization occurs.
The proper sequence of these events is
A. 4, 6, 7, 3, 2, 5, 1.
B. 4, 6, 7, 1, 2, 3, 5.
C. 6, 7, 4, 1, 2, 3, 5.
D. 2, 4, 6, 7, 1, 3, 5.
E. 4, 2, 5, 6, 7, 3, 1.
ANSWER
In which of the following would the rate of impulse conduction be the greater?
A. a myelinated fiber
B. a nonmyelinated fiber
ANSWER
In which of the following would the rate of impulse conduction be the greater?
A. a myelinated fiber
B. a nonmyelinated fiber
Small phagocytic cells that are especially obvious in damaged tissue in the CNS are the
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
ANSWER
Small phagocytic cells that are especially obvious in damaged tissue in the CNS are the
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
Interneurons
A. are found only in the central nervous system.
B. carry only sensory impulses.
C. carry only motor impulses.
D. only connect motor neurons to other motor
neurons.
E. are found between neurons and their
effectors.
ANSWER
Interneurons
A. are found only in the central nervous system.
B. carry only sensory impulses.
C. carry only motor impulses.
D. only connect motor neurons to other motor neurons.
E. are found between neurons and their effectors.
The sodium–potassium exchange pump
A. must reestablish ion concentrations after each action potential.
B. transports sodium ions into the cell during depolarization.
C. transports potassium ions out of the cell during repolarization.
D. moves sodium and potassium in the direction of their chemical gradients.
E. requires ATP to function.
ANSWER
The sodium–potassium exchange pump
A. must reestablish ion concentrations after each action potential.
B. transports sodium ions into the cell during depolarization.
C. transports potassium ions out of the cell during repolarization.
D. moves sodium and potassium in the direction of their chemical gradients.
E. requires ATP to function.
In which of the following would the rate of impulse conduction be the greatest?
A. a myelinated fiber 20 microns in diameter
B. a nonmyelinated fiber 20 microns in diameter
C. a myelinated fiber 2 microns in diameter
D. a nonmyelinated fiber 2 microns in diameter
E. a nonmyelinated fiber 25 cm long
ANSWER
In which of the following would the rate of impulse conduction be the greatest?
A. a myelinated fiber 20 microns in diameter
B. a nonmyelinated fiber 20 microns in diameter
C. a myelinated fiber 2 microns in diameter
D. a nonmyelinated fiber 2 microns in diameter
E. a nonmyelinated fiber 25 cm long
Neuroglial cells found surrounding the cell bodies of peripheral neurons are
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
ANSWER
Neuroglial cells found surrounding the cell bodies of peripheral neurons are
A. astrocytes.
B. satellite cells.
C. oligodendrocytes.
D. microglia.
E. ependymal cells.
If the presynaptic membrane of a motor neuron
suddenly became permeable to calcium ion,
A. the neuron would fatigue.
B. the motor end plate would be stimulated.
C. the motor end plate would be inhibited.
D. no neurotransmitter would be released.
E. the neuron would not be able to stimulate the muscle.
ANSWER
If the presynaptic membrane of a motor neuron
suddenly became permeable to calcium ion,
A. the neuron would fatigue.
B. the motor end plate would be stimulated.
C. the motor end plate would be inhibited.
D. no neurotransmitter would be released.
E. the neuron would not be able to stimulate the muscle.
The effect of a particular neurotransmitter is dependent upon the properties of the _____, not the _____.
A. neurotransmitter; receptor
B. receptor; neurotransmitter
C. substrate; receptor
D. hormone; neurotransmitter
E. propagation; neurotransmitter
ANSWER
The effect of a particular neurotransmitter is dependent upon the properties of the _____, not the _____.
A. neurotransmitter; receptor
B. receptor; neurotransmitter
C. substrate; receptor
D. hormone; neurotransmitter
E. propagation; neurotransmitter
The all-or-none principle states that
A. all stimuli will produce identical action potentials.
B. all stimuli great enough to bring the membrane to
threshold will produce identical action potentials.
C. the greater the magnitude of the stimuli, the greater
the intensity of the action potential.
D. only sensory stimuli can activate action potentials.
E. only motor stimuli can activate action potentials.
ANSWER
The all-or-none principle states that
A. all stimuli will produce identical action potentials.
B. all stimuli great enough to bring the membrane to
threshold will produce identical action potentials.
C. the greater the magnitude of the stimuli, the greater
the intensity of the action potential.
D. only sensory stimuli can activate action potentials.
E. only motor stimuli can activate action potentials.
Tom’s father suffers a stroke that leaves him partially paralyzed on his right side. What type of neuroglial cell would you expect to find in increased numbers in the area of the brain that is affected by the stroke?
A. astrocytes
B. satellite cells
C. oligodendrocytes
D. microglia
E. ependymal cells
ANSWER
Tom’s father suffers a stroke that leaves him partially paralyzed on his right side. What type of neuroglial cell would you expect to find in increased numbers in the area of the brain that is affected by the stroke?
A. astrocytes
B. satellite cells
C. oligodendrocytes
D. microglia
E. ependymal cells
Which of the following is not a neuroglialcell of the nervous system?
A. Schwann cells
B. neurons
C. ependymal cells
D. microglia
E. satellite cells
ANSWER
Which of the following is not a neuroglialcell of the nervous system?
A. Schwann cells
B. neurons
C. ependymal cells
D. microglia
E. satellite cells
Tetradotoxin is a toxin that blocks the chemically activated sodium channels from opening. What effect would this have on the function of neurons?
A. Neurons would depolarize more rapidly.
B. Action potentials would lack a repolarization phase.
C. The absolute refractory period would be shorter than normal.
D. The neuron would be unable to propagate action potentials.
E. The toxin would not interfere with neuron function because the voltage-regulated sodium channels would still function.
ANSWER
Tetradotoxin is a toxin that blocks the chemically activated sodium channels from opening. What effect would this have on the function of neurons?
A. Neurons would depolarize more rapidly.
B. Action potentials would lack a repolarization phase.
C. The absolute refractory period would be shorter than normal.
D. The neuron would be unable to propagate action potentials.
E. The toxin would not interfere with neuron function because the voltage-regulated sodium channels would still function.
In a condition known as hypocalcemia, the level of calcium ions in the blood and interstitial fluid is lower than normal. How would this condition affect the function of the nervous system?
A. Cholinergic synapses would be more active.
B. Neurons would generate action potentials spontaneously.
C. Less neurotransmitter would be released from a presynaptic membrane in response to an action potential.
D. Depolarizing events would occur more frequently at the postsynaptic membrane.
E. Potassium channels would fail to open.
ANSWER
In a condition known as hypocalcemia, the level of calcium ions in the blood and interstitial fluid is lower than normal. How would this condition affect the function of the nervous system?
A. Cholinergic synapses would be more active.
B. Neurons would generate action potentials spontaneously.
C. Less neurotransmitter would be released from a presynaptic membrane in response to an action potential.
D. Depolarizing events would occur more frequently at the postsynaptic membrane.
E. Potassium channels would fail to open.
Cells responsible for information processing and transfer are the
A. neuroglia.
B. Schwann cells.
C. neurons.
D. astrocytes.
E. microglia.
ANSWER
Cells responsible for information processing and transfer are the
A. neuroglia.
B. Schwann cells.
C. neurons.
D. astrocytes.
E. microglia.
Which of the following is a function of the
neuroglia?
A. Information transfer
B. Bringing sensory impulses into the CNS
C. Sending instructions to the effector organs
D. Secretion of cerebrospinal fluid
ANSWER
Which of the following is a function of the
neuroglia?
A. Information transfer
B. Bringing sensory impulses into the CNS
C. Sending instructions to the effector organs
D. Secretion of cerebrospinal fluid
During saltatory conduction,
A. action potentials move in all directions along an axon.
B. action potentials occur at successive nodes along the length of the stimulated axon.
C. local currents depolarize adjacent areas of membrane so that action potentials continue to form along the membrane.
D. action potentials produce a local current that is strong enough to spread along the length of the axon.
E. local potentials produce a continuous outward flow of potassium ions.
ANSWER
During saltatory conduction,
A. action potentials move in all directions along an axon.
B. action potentials occur at successive nodes along the length of the stimulated axon.
C. local currents depolarize adjacent areas of membrane so that action potentials continue to form along the membrane.
D. action potentials produce a local current that is strong enough to spread along the length of the axon.
E. local potentials produce a continuous outward flow of potassium ions.
Aggregations of fixed and free ribosomes in neurons are referred to as
A. neurofilaments.
B. neurofibrils.
C. perikaryon.
D. Nissl bodies.
E. microglia.
ANSWER
Aggregations of fixed and free ribosomes in neurons are referred to as
A. neurofilaments.
B. neurofibrils.
C. perikaryon.
D. Nissl bodies.
E. microglia.
Which of the following is NOT true regarding the refractory period?
A. The refractory period is the time in which an excitable cell cannot generate another action potential
B. The absolute refractory period coincides with the sodium channel activation and inactivation
C. The refractory period include a hyperpolarization period
D. The relative refractory period is the time during which a second action potential can be initiated, but only by a suprathreshold stimulus
ANSWER
Which of the following is NOT true regarding the refractory period?
A. The refractory period is the time in which an excitable cell cannot generate another action potential
B. The absolute refractory period coincides with the sodium channel activation and inactivation
C. The refractory period include a hyperpolarization period
D. The relative refractory period is the time during which a second action potential can be initiated, but only by a suprathreshold stimulus
Newly synthesized neurotransmitters travel from the cell body to the synaptic end bulb via
A. Retrograde flow
B. Anterograde transport
C. Blood vessels
D. Connective tissue
E. Cerebrospinal fluid
ANSWER
Newly synthesized neurotransmitters travel from the cell body to the synaptic end bulb via
A. Retrograde flow
B. Anterograde transport
C. Blood vessels
D. Connective tissue
E. Cerebrospinal fluid
Which of the following does not influence the time necessary for a nerve impulse to be transmitted?
A. length of the axon
B. presence or absence of a myelin sheath
C. diameter of the axon
D. presence or absence of nodes
E. whether the axon is sensory or motor
ANSWER
Which of the following does not influence the time necessary for a nerve impulse to be transmitted?
A. length of the axon
B. presence or absence of a myelin sheath
C. diameter of the axon
D. presence or absence of nodes
E. whether the axon is sensory or motor
In which of the following would the rate
of impulse conduction be the slowest?
A. a type A fiber
B. a type B fiber
C. a type C fiber
D. a type D fiber
E. a type E fiber
ANSWER
In which of the following would the rate
of impulse conduction be the slowest?
A. a type A fiber
B. a type B fiber
C. a type C fiber
D. a type D fiber
E. a type E fiber
The axon is connected to the soma by the
A. telodendria.
B. synaptic knobs.
C. collaterals.
D. hillock.
E. synapse.
ANSWER
The axon is connected to the soma by the
A. telodendria.
B. synaptic knobs.
C. collaterals.
D. hillock.
E. synapse.
_____ neurons are the most common neuron in the CNS.
A. Multipolar
B. Anaxonic
C. Unipolar
D. Bipolar
E. none of the above
ANSWER
_____ neurons are the most common neuron in the CNS.
A. Multipolar
B. Anaxonic
C. Unipolar
D. Bipolar
E. none of the above
The ion needed to initiate the release of
acetylcholine into the synaptic cleft is
A. sodium.
B. potassium.
C. calcium.
D. chloride.
E. zinc.
ANSWER
The ion needed to initiate the release of
acetylcholine into the synaptic cleft is
A. sodium.
B. potassium.
C. calcium.
D. chloride.
E. zinc.
In which of the following would the rate of impulse conduction be the greatest?
A. a type A fiber
B. a type B fiber
C. a type C fiber
D. a type D fiber
E. a type E fiber
ANSWER
In which of the following would the rate of impulse conduction be the greatest?
A. a type A fiber
B. a type B fiber
C. a type C fiber
D. a type D fiber
E. a type E fiber
Branches that sometimes occur along the length of an axon are called
A. telodendria.
B. synaptic knobs.
C. collaterals.
D. hillocks.
E. synapses.
ANSWER
Branches that sometimes occur along the length of an axon are called
A. telodendria.
B. synaptic knobs.
C. collaterals.
D. hillocks.
E. synapses.
_____ neurons form the afferent division of the PNS.
A. Visceral sensory
B. Sensory
C. Neural sensory
D. Somatic sensory
E. none of the above
ANSWER
_____ neurons form the afferent division of the PNS.
A. Visceral sensory
B. Sensory
C. Neural sensory
D. Somatic sensory
E. none of the above
__________ neurons process information
in the CNS and connect neuron to neuron
A. afferent
B. sensory
C. interneuron
D. motor
E. efferent
ANSWER
__________ neurons process information
in the CNS and connect neuron to neuron
A. afferent
B. sensory
C. interneuron
D. motor
E. efferent
Which of the following comparisons between neurons and muscle tissue is incorrect?
A. Resting potentials are greater in muscle fibers.
B. Muscle fibers conduct action potentials at relatively slower speeds.
C. Action potentials last longer in muscle fibers.
D. Muscle fibers only conduct action potentials via continuous conduction.
E. Action potentials are completed more quickly in muscle fibers.
ANSWER
Which of the following comparisons between neurons and muscle tissue is incorrect?
A. Resting potentials are greater in muscle fibers.
B. Muscle fibers conduct action potentials at relatively slower speeds.
C. Action potentials last longer in muscle fibers.
D. Muscle fibers only conduct action potentials via continuous conduction.
E. Action potentials are completed more quickly in muscle fibers.
_____ are the most numerous type of neuron.
A. Sensory neurons
B. Motor neurons
C. Multipolar neurons
D. Bipolar neurons
E. Interneurons
ANSWER
_____ are the most numerous type of neuron.
A. Sensory neurons
B. Motor neurons
C. Multipolar neurons
D. Bipolar neurons
E. Interneurons
Membrane channels that are always open
are called _____ channels.
A. active
B. gated
C. leakage
D. regulated
E. local
ANSWER
Membrane channels that are always open
are called _____ channels.
A. active
B. gated
C. leakage
D. regulated
E. local
Which type of synapse dominates the nervous system?
A. chemical
B. electrical
C. mechanical
D. processing
E. radiative
ANSWER
Which type of synapse dominates the nervous system?
A. chemical
B. electrical
C. mechanical
D. processing
E. radiative
Neurotransmitters are released from the
A. telodendria.
B. synaptic end bulbs.
C. collaterals.
D. hillock.
E. synapse.
ANSWER
Neurotransmitters are released from the
A. telodendria.
B. synaptic end bulbs.
C. collaterals.
D. hillock.
E. synapse.
Which of the following are types of neuroglia?
A. ependymal cells
B. microglia
C. astrocytes
D. oligodendrocytes
E. all of the above
ANSWER
Which of the following are types of neuroglia?
A. ependymal cells
B. microglia
C. astrocytes
D. oligodendrocytes
E. all of the above
Any stimulus that opens a _____ channel
will produce a graded potential.
A. gated
B. voltage regulated
C. active
D. non-gated
E. leakage
ANSWER
Any stimulus that opens a _____ channel
will produce a graded potential.
A. gated
B. voltage regulated
C. active
D. non-gated
E. leakage
Novocaine is a local anesthetic that blocks pain
signals. Its works by
A. Preventing opening of voltage-gated sodium channels
B. Inhibiting the action potential at the soma
C. Preventing reuptake of the neurotransmitter at the
post-synaptic cell
D. Preventing closing of voltage-gated potassium
channels in the dendrites
E. Shutting down the sodium-potassium pumps
ANSWER
Novocaine is a local anesthetic that blocks pain signals. Its works by
A. Preventing opening of voltage-gated sodium channels
B. Inhibiting the action potential at the soma
C. Preventing reuptake of the neurotransmitter at the post-synaptic cell
D. Preventing closing of voltage-gated potassium channels in the dendrites
E. Shutting down the sodium-potassium pumps
The rabies virus can travel to the CNS via
A. axoplasmic transport.
B. retrograde flow.
C. blood vessels.
D. connective tissue.
E. CSF.
ANSWER
The rabies virus can travel to the CNS via
A. axoplasmic transport.
B. retrograde flow.
C. blood vessels.
D. connective tissue.
E. CSF.
_____ account for roughly half of the volume of the nervous system.
A. Axons
B. Dendrites
C. Neuroglia
D. Synapses
E. Efferent fibers
ANSWER
_____ account for roughly half of the volume of the nervous system.
A. Axons
B. Dendrites
C. Neuroglia
D. Synapses
E. Efferent fibers
A part of the neuron that normally
receives stimuli is called
A. An axon
B. A dendrite
C. A neurolemma
D. A schwann cell
ANSWER
A part of the neuron that normally
receives stimuli is called
A. An axon
B. A dendrite
C. A neurolemma
D. A schwann cell
In what way does the interior surface of a
cell membrane of a resting neuron differ
from the external environment? The
interior is
A. Positively charged and contains less sodium
B. Negatively charged and contains less sodium
C. Negatively charged and contains more sodium
D. Positively charged and contains more sodium
ANSWER
In what way does the interior surface of a cell membrane of a resting neuron differ from the external environment? The interior is
A. Positively charged and contains less sodium
B. Negatively charged and contains less sodium
C. Negatively charged and contains more sodium
D. Positively charged and contains more sodium
