Deck 13: The Nervous System

Question 1

The mode of action of Ecstasy is to

A) cause overstimulation of target cells in the brain.
B) interfere with release of neurotransmitters in the brain.
C) decreases the amount of serotonin in the brain.
D) speed up clearance of serotonin in the brain.
E) is used clinically to treat anxiety.

Answer 1

A

Question 2

Which cells relay signals from the interneurons to the body's effectors?

A) sensory neurons
B) neuroglia
C) motor neurons
D) association neurons
E) dendritic cells

Answer 2

C

Question 3

The principal job of the human nervous system is to

A) facilitate communication among the body systems.
B) store information.
C) replace or repair damaged tissues.
D) provide for defense against pathogens.
E) rid the body of metabolic wastes.

Answer 3

A

Question 4

Functionally speaking, a nerve impulse is

A) a flow of electrons along the outside of the plasma membrane of a neuron.
B) the movement of cytoplasmic elements through the core of the neuron.
C) a series of changes in membrane potentials.
D) a lengthening and shortening of the membrane extensions of an individual neuron.
E) a change in the metabolic rate within a neuron.

Question 5

The resting potential of a neuron is approximately

A) - 70 microvolts.
B) - 70 millivolts.
C) - 70 volts.
D) - 70 electrovolts.
E) - 70 megavolts.

Question 6

What percentage of the nervous system is made up of neuroglia?

A) twenty
B) fifty
C) sixty
D) seventy five
E) ninety

Question 7

Neuroglial cells do all of the following EXCEPT

A) metabolically support other neurons.
B) form sheaths around neurons and control the rate of impulse transmission.
C) form more than half of the volume of the brain.
D) provide physical support.
E) conduct action potentials.

Question 8

Which of the following is NOT true concerning sensory neurons?

A) They collect information about stimuli.
B) They lie in the pathway between the interneurons and motor neurons.
C) They relay information to the spinal cord.
D) They relay information to the brain.
E) They are one of three types of neurons.

Question 9

The active ingredient in the popular drug Ecstasy is related to

A) heroin.
B) cocaine.
C) codeine.
D) amphetamine.
E) serotonin.

Question 10

Within a single neuron, the direction an impulse follows is

A) dendrite >>> axon >>> cell body.
B) axon >>> dendrite >>> cell body.
C) dendrite >>> cell body >>> axon.
D) cell body >>> dendrite >>> axon.
E) cell body >>> axon >>> dendrite.

Question 11

When an impulse passes from one neuron to the next, it

A) is passed directly from dendrite to axon.
B) passes from axon to cell body to dendrite.
C) can bypass the cell bodies of both axon and dendrite.
D) passes from axon to dendrite.
E) undergoes repolarization.

Question 12

The basic unit of the nervous system is

A) the neuron.
B) neuroglia.
C) the brain.
D) a nerve.
E) a nerve impulse.

Question 13

At rest, a nerve cell has a high concentration of ____ inside and a high concentration of ____ outside.

A) acetylcholine; chlorine
B) sodium; potassium
C) potassium; sodium
D) calcium; phosphorus
E) phosphorus; calcium

Question 14

When a neuron is at rest,

A) there is a voltage difference across the membrane of about + 70 millivolts.
B) the interior is positively charged.
C) it is responding to a stimulus.
D) the fluid outside the membrane has more sodium and less potassium than the cytoplasm.
E) axons are firing at a faster rate.

Question 15

What percentage of the nervous system is made up of neurons?

A) five
B) ten
C) fifteen
D) twenty
E) fifty

Question 16

Which of the following is the first response a neuron makes to a stimulus?

A) Sodium ions enter the cell.
B) Sodium ions leave the cell.
C) Potassium ions enter the cell.
D) Potassium ions leave the cell.
E) Calcium ions leave the cell.

Question 17

Resting membrane potential may be defined as

A) the difference of charge between cytoplasmic side of cell's membrane and outer membrane side of cell.
B) a positive charge.
C) an action potential.
D) axon generated.
E) a nerve impulse.

Question 18

Long term use of Ecstasy can lead to

A) chronic fevers.
B) chronic rapid heart rate.
C) memory loss.
D) kidney failure.
E) liver failure.

Question 19

The steady charge difference across the plasma membrane is called the

A) action potential.
B) energy potential.
C) electrolyte potential.
D) resting membrane potential.
E) kinetic potential.

Question 20

The single long process that extends from a typical motor nerve cell is the

A) axon.
B) neuron.
C) synapse.
D) dendrite.
E) cell body.

Question 21

How long does the spike of an action potential last?

A) one second
B) one millisecond
C) one microsecond
D) one half second
E) one nanosecond

Question 22

The occurrence of an action potential can best be compared to a

A) switch to turn a lamp on and off.
B) volume control on a stereo.
C) door to a classroom.
D) room light dimmer switch.
E) gradually inclined ramp.

Question 23

What happens immediately following the closing of the sodium gates during an action potential?

A) Sodium ions enter the cell.
B) Sodium ions leave the cell.
C) Potassium ions enter the cell.
D) Potassium ions leave the cell.
E) Calcium ions leave the cell.

Question 24

The phrase "all or nothing," used in conjunction with discussion about an action potential, means that

A) a resting membrane potential has been received by the cell.
B) nothing can stop the action potential once the threshold is reached.
C) the membrane either achieves total equilibrium or remains as far from equilibrium as possible.
D) propagation along the neuron is saltatory.
E) the action potential is strong.

Question 25

During the passage of a nerve impulse all of the following occur EXCEPT

A) sodium ions pass through gated channels.
B) positive feedback causes more sodium ions to enter the cell.
C) the interior of the cell becomes positive.
D) changing voltage increases the number of open gates.
E) changing voltage decreases the number of open gates.

Question 26

Which is a junction between two neurons?

A) Schwann cell
B) chemical synapse
C) node
D) sodium gate
E) voltage gate

Question 27

Transmitter substances

A) are expelled from the presynaptic cells.
B) tend to destroy acetylcholine.
C) enter the presynaptic cell to continue the passage of the impulse.
D) interact with membrane receptors of the postsynaptic cells.
E) are expelled from the presynaptic cells and interact with membrane receptors of the postsynaptic cells.

Question 28

The operation of a synapse

A) results from the passage of an electrical charge across the gap.
B) involves a transmitter substance from vesicles in the presynaptic neuron that acts upon a receptor site in the postsynaptic neuron.
C) occurs only between two nerves.
D) is limited only by the action of acetylcholinesterase.
E) requires neurotransmitter to pass directly through the plasma membrane of a postsynaptic nerve.

Question 29

Once a threshold is reached,

A) the number of sodium gates that open depends upon the strength of a stimulus.
B) a graded local potential will be unable to spread to a trigger zone of the nerve membrane.
C) the resting potential of a neuron is restored.
D) the potassium channels in the input zone open.
E) the opening of sodium gates and the accompanying flow of sodium ions is an example of positive feedback.

Question 30

Which of the following helps to create the electric gradient?

A) negatively charged proteins
B) positively charged proteins
C) neutral proteins
D) cholesterol in the cell membrane
E) hydrogen ions in the cytoplasm

Question 31

During the recovery period between action potentials,

A) the threshold value is increased.
B) the threshold value is reduced.
C) the sodium gates are shut and the potassium gates are opened.
D) both the sodium and the potassium gates are shut.
E) the nerve is said to be at the resting potential.

Question 32

The presynaptic neuron and postsynaptic neuron do not directly contact each other because

A) one would inhibit the actions of the other.
B) they never grow to sufficient length.
C) the synaptic vesicles keep them apart.
D) this would cause continuous impulse transmission.
E) acetylcholine prevents this action.

Question 33

Disturbances in sensory neurons will result in an action potential if the

A) stimulus is graded.
B) stimulus remains local.
C) graded stimulus reaches a trigger zone.
D) localized stimuli do not spread far.
E) stimuli become downgraded to localized ones.

Question 34

Chemical signaling molecules that diffuse across a chemical synapse are called

A) neurotransmitters.
B) enzymes.
C) neurostimulators.
D) neuron releasing factors.
E) ion carriers.

Question 35

An action potential is brought about by

A) a sudden membrane impermeability.
B) the movement of negatively charged proteins through the neuronal membrane.
C) the movement of lipoproteins to the outer membrane.
D) a local change in membrane permeability caused by a greater-than-threshold stimulus.
E) the movement of negatively charged amino acids through the neuronal membrane.

Question 36

The membrane-bound enzyme system that restores and maintains the resting membrane potential is which of the following pumps?

A) sodium-phosphorus
B) sodium-potassium
C) sodium-chlorine
D) phosphorus-calcium
E) phosphorus-chlorine

Question 37

Which of the following occurs first during an action potential?

A) Many sodium ions flow into the neuron.
B) Voltage-gated sodium channels open.
C) A local disturbance triggers the resting voltage to exceed the threshold level.
D) The interior of the neuron becomes positive.
E) The interior of the neuron becomes negative.

Question 38

Which statement is false?

A) A nerve will not fire unless a stimulus exceeds the threshold.
B) An action potential is an all-or-nothing event.
C) An action potential continues indefinitely until a quenching signal is released.
D) An action potential is self-propagating.
E) An action potential transmission depends on activities at the membrane.

Question 39

Active transport may be described as all of the following EXCEPT

A) is concerned with establishing the resting potential of a neuron.
B) counters the process of diffusion.
C) allows transport of atoms across the plasma membrane of the neuron against the concentration gradient.
D) uses energy to power transport.
E) physically blocking transport.

Question 40

For sodium to accumulate rapidly inside a neuron cell membrane,

A) a stimulus above the threshold must open sodium gates in an accelerating manner.
B) the wave of repolarization must occur to reestablish a resting potential.
C) there must be a dramatic increase in the negative charge of the cytoplasm.
D) a voltage surge must cause the sodium gates to close.
E) the potassium gates must open first.

Question 41

In the central nervous system, nerves are called

A) reflex arcs.
B) nerve tracts.
C) nerve pathways.
D) neurofibers.
E) monosynaptic paths.

Question 42

Transmitter substances may be described as all of the following EXCEPT

A) include acetylcholine.
B) change the permeability of postsynaptic cells.
C) may be excitatory or inhibitory.
D) may participate in synaptic integration.
E) ions.

Question 43

What bridges the gap between a sending and a receiving neuron?

A) threshold value
B) action potential
C) transmitter substance
D) neurohormone
E) neuromodulator

Question 44

Endorphins are

A) neuromodulators.
B) stimulators of brain and nervous activity.
C) inhibitors of pain perception.
D) neuromodulators and stimulators of brain and nervous activity.
E) neuromodulators and inhibitors of pain perception.

Question 45

Synaptic integration means

A) all positive or excitatory stimuli are added together.
B) the positive and negative ions neutralize each other.
C) excitatory and inhibitory signals are combined in a neuron.
D) the adjacent neurons interact so that excitatory and inhibitory stimuli cancel each other out.
E) that an interneuron is involved.

Question 46

Which statement is false?

A) Reflexes are the simplest of all nervous reactions.
B) Reflexes are automatic responses.
C) Motor neurons lead toward the brain or central nervous system.
D) Reflex actions are stereotyped and repeatable.
E) Sensory neurons conduct impulses from the receptor to the central nervous system.

Question 47

The neurotransmitter serotonin performs all of the following functions EXCEPT

A) helps control sleep
B) is involved with sensory perception
C) regulates body temperature
D) helps control emotional states
E) speed up heart rate

Question 48

Nitric oxide works by

A) inhibiting reuptake.
B) enzyme degradation of neurotransmitter.
C) stimulating reuptake.
D) dilating blood vessels.
E) inhibiting release of other neurotransmitters.

Question 49

Which of the following drugs acts to block reuptake of neurotransmitters?

A) aspirin
B) acetylcholine
C) Prozac
D) NSAIDS
E) nicotine

Question 50

The spaces that separate adjacent Schwann cells are called

A) neuroglia.
B) myelin sheaths.
C) nodes.
D) dendrites.
E) synapses.

Question 51

Saltatory ("jumping") conduction

A) occurs only in the central nervous system.
B) is a quicker type of nerve conduction.
C) occurs between nerves and muscles.
D) involves the movement of impulses from node to node.
E) involves both a quicker type of nerve conduction and the movement of impulses from node to node.

Question 52

GABA works by

A) inhibiting reuptake.
B) enzyme degradation of neurotransmitter.
C) stimulating reuptake.
D) dilating blood vessels.
E) inhibiting release of other neurotransmitters.

Question 53

The myelin sheath

A) is formed by the Schwann cell.
B) speeds up the transmission of impulses.
C) does not surround all nerves.
D) extends from node to node.
E) all of these

Question 54

Which of the following neurotransmitters prepares the body to respond to stress or excitement?

A) acetylcholine
B) dopamine
C) epinephrine
D) serotonin
E) endorphins

Question 55

Which chemical controls blood vessel dilation?

A) acetylcholine
B) nitric oxide
C) serotonin
D) endorphins
E) dopamine

Question 56

At an inhibitory synapse,

A) no transmitter substances are released by the sending cell.
B) a transmitter substance produces changes in the receiving cell that drive the membrane potential away from threshold.
C) no transmitter substance can bind to the receiving cell.
D) a transmitter substance produces changes in the receiving cell that drive the membrane potential closer to threshold.
E) a transmitter is degraded by an enzyme.

Question 57

The use of transport proteins to return a neurotransmitter from the synapse back to the presynaptic cells is called

A) enzymatic breakdown.
B) diffusion.
C) repackaging.
D) storage.
E) reuptake.

Question 58

A deterioration in the myelin sheaths of motor axons to the lower leg would be expected to

A) remove the restraints to ion movement and speed up impulse transmission.
B) cause immobility of the leg due to cessation of impulses to leg muscles.
C) slow the rate of transmission and cause lack of motor control.
D) have little effect because the sheaths are for insulation only.
E) cause paralysis.

Question 59

The Schwann cell's counterpart in the central nervous system is the

A) microglial cell.
B) astrocytes.
C) ependymal cells.
D) oligodendrocytes.
E) satellite cells.

Question 60

An excitatory postsynaptic potential

A) is only one of several types of graded potential.
B) has a hyperpolarizing effect.
C) will drive the membrane away from its threshold.
D) is summed with an inhibitory postsynaptic potential at the input zone of a neuron in a process known as synaptic integration.
E) help keep the membrane at resting membrane potential.

Question 61

Neurons that synapse back on themselves create

A) action potentials.
B) reverberating circuits.
C) repeat pathways.
D) blocked impulses.
E) weak action potentials.

Question 62

All nerves that lead away from the central nervous system are

A) efferent nerves.
B) sensory nerves.
C) afferent nerves.
D) spinal nerves.
E) peripheral nerves.

Question 63

The two MAJOR divisions of the nervous system are the

A) autonomic and peripheral systems.
B) sympathetic and parasympathetic systems.
C) cranial and spinal nerves.
D) central and peripheral nervous systems.
E) brain and spinal cord.

Question 64

The two principal divisions of the peripheral nervous system are the

A) somatic and autonomic systems.
B) sympathetic and parasympathetic systems.
C) peripheral and central systems.
D) afferent and autonomic systems.
E) cranial and skeletal nerves.

Question 65

The simplest nerve pathway is

A) located in the midbrain.
B) the reflex pathway.
C) found in the lower part of the brain.
D) found in the autonomic nervous system.
E) in the flow of information from a sense receptor to the brain.

Question 66

By definition, a nerve is

A) a bundle of axons.
B) a single extension of a neuron.
C) the same as a neuron within the central nervous system.
D) a dendrite.
E) a fiber more than 10 inches in length.

Question 67

The central nervous system includes

A) the brain.
B) the spinal cord
C) interneurons
D) all of these.
E) a and b only.

Question 68

Clusters of cell bodies of neurons outside the central nervous system are known as

A) nerve cords.
B) ganglia.
C) a plexus.
D) notochords.
E) nerves.

Question 69

One example of a simple reflex involves the

A) contraction of a muscle when it is stretched.
B) conscious message to move part of the body.
C) receptor, the brain, and the effector.
D) muscle action in a salute when a noncommissioned serviceman sees an officer.
E) contraction of an antagonistic muscle when its opposite muscle relaxes.

Question 70

The human brain contains at least ____ neurons.

A) 100 billion
B) 100 million
C) 500 million
D) 100 thousand
E) 50 million

Question 71

Which of the following statements concerning the peripheral nervous system is false?

A) Spinal nerves lead to and from the spinal cord.
B) There are 31 pairs of spinal nerves.
C) Cranial nerves lead from the brain directly to the spinal cord.
D) Some nerves carry only sensory information.
E) Some nerves are both sensory and motor.

Question 72

In the knee-jerk reflex arc, the synapse between a sensory neuron and a motor neuron occurs where?

A) in the brain
B) between the receptor and the spinal cord
C) within the muscle of the leg
D) within the spinal cord
E) in the nerve leading to the spinal cord

Question 73

The two main divisions of the nervous system are

A) somatic and autonomic.
B) sensory and motor.
C) central and peripheral.
D) sympathetic and parasympathetic.
E) skeletal and visceral.

Question 74

The stretch reflex

A) is an adaptation that enables humans to hold objects steadily for extended periods if time.
B) is activated by stretch-sensitive receptors inside the muscle spindles.
C) is a simple, stereotyped, and repeatable motor action.
D) is elicited by a sensory stimulus.
E) all of these

Question 75

Which of the following would NOT be a part of the central nervous system?

A) brain
B) interneurons
C) spinal cord
D) spinal nerves
E) neuroglia cells

Question 76

Sensory signals are also referred to as

A) efferent.
B) motor.
C) reverberating.
D) saltatory.
E) afferent.

Question 77

Motor signals are also referred to as

A) efferent.
B) motor.
C) reverberating.
D) saltatory.
E) afferent.

Question 78

The pathway for a simple reaction to a stimulus is

A) sense organ, sensory neuron, association neuron, motor neuron, effector.
B) sense organ, sensory neuron, motor neuron, association neuron, effector.
C) sense organ, motor neuron, sensory neuron, association neuron, effector.
D) sense organ, motor neuron, association neuron, sensory neuron, effector.

Question 79

The autonomic subdivision consists specifically of

A) central and peripheral nerves.
B) parasympathetic and sympathetic nerves.
C) somatic and involuntary nerves.
D) brain and spinal cord nerves.
E) spinal and cranial nerves.

Question 80

The autonomic subdivision of the vertebrate nervous system would innervate all but which of the following?

A) intestinal muscles
B) skeletal muscles
C) heart
D) pancreas
E) liver