Deck 9: Nervous System

Question 1

Efferent neurons carry impulses from the central nervous system to effectors.

Answer 1

True

Question 2

If fibers in an ascending tract of the spinal cord are cut,the affected person will have a loss of motor functions below the injury.

Answer 2

False

Question 3

The gray commissure of the spinal cord surrounds the central canal.

Answer 3

True

Question 4

The arbor vitae is part of the cerebrum.

Question 5

Sympathetic tone is defined as ongoing stimulation of smooth muscles in the walls of blood vessels,which results in partial constriction.

Question 6

A deficiency of calcium in the body can result in involuntary muscle contractions.

Question 7

Interneurons are specialized to carry impulses from peripheral receptors into the brain or spinal cord.

Question 8

Sensory nerves carry information to effectors.

Question 9

Most nerves of the body are mixed nerves.

Question 10

Afferent neurons bring sensory information into the central nervous system.

Question 11

A nerve is a single neuron.

Question 12

The subarachnoid space within the meninges contains cerebrospinal fluid.

Question 13

A synapse is the functional connection between two neurons.

Question 14

A neuron may release more than one type of neurotransmitter.

Question 15

Cell bodies of motor neurons are located in the anterior horns of the spinal cord.

Question 16

The butterfly shape seen in a cross section of the spinal cord is composed of white matter.

Question 17

Nodes of Ranvier connect adjacent neurons.

Question 18

Astrocytes provide structural support in the nervous system.

Question 19

Brain damage to the temporal lobe,where recent memory is processed,can result in the inability to form long-term memory.

Question 20

An action potential is an all-or-none response.

Question 21

Ischemic cell damage is caused by a lack of blood flow,which deprives cells of

A) sodium ions.
B) potassium ions.
C) oxygen.
D) carbon dioxide.
E) chloride ions.

Question 22

Which describes the ion concentrations inside and outside of a neuron?

A) Sodium and potassium ions are both at higher concentration on the inside of the cell.
B) Sodium and potassium ions are both at higher concentration on the outside of the cell.
C) The sodium ion concentration is higher on the inside of the cell and potassium ion concentration is higher on the outside of the cell.
D) The sodium ion concentration is higher on the outside of the cell and potassium ion concentration is higher on the inside of the cell.
E) The concentrations of sodium and potassium ions are both equal inside and outside of the cell.

Question 23

An infant's responses to stimuli are coarse and undifferentiated because its nerve fibers

A) have not yet appeared.
B) are not yet capable of action potentials.
C) have not yet developed connections to the brain.
D) are not completely myelinated.
E) cannot release neurotransmitter.

Question 24

The first component of a reflex arc is a(n)

A) effector.
B) receptor.
C) central nervous system.

Question 25

During an action potential,depolarization occurs as a result of

A) potassium ions diffusing to the outside of the cell membrane.
B) potassium ions diffusing to the inside of the cell membrane.
C) sodium ions diffusing to the outside of the cell membrane.
D) sodium ions diffusing to the inside of the cell membrane.
E) sodium and potassium ions not diffusing.

Question 26

During an action potential,repolarization occurs as a result of

A) potassium ions diffusing to the outside of the cell membrane.
B) potassium ions diffusing to the inside of the cell membrane.
C) sodium ions diffusing to the outside of the cell membrane.
D) sodium ions diffusing to the inside of the cell membrane.
E) sodium and potassium ions not diffusing.

Question 27

Masses of myelinated nerve fibers appear

A) white.
B) gray.
C) brown.
D) transparent.
E) red.

Question 28

The simplest nerve pathway in the body is called a(n)

A) reflex arc.
B) effector route.
C) reception path.
D) output relay.

Question 29

In the case of a subdural hematoma (blood accumulating beneath the dura)resulting from a blow to the head,blood accumulates

A) between the dura mater and the bone of the skull.
B) between the dura mater and arachnoid mater.
C) between the pia mater and brain.
D) between the arachnoid mater and pia mater.
E) between the subarachnoid space.

Question 30

The olfactory nerves and optic nerves are mixed nerves.

Question 31

Cranial nerves connect the brain only to head and neck regions;spinal nerves connect all regions below the neck.

Question 32

When a neuron increases its release of neurotransmitter in response to a nerve impulse,as a result of repeated stimulation,it is said to be

A) facilitated.
B) amplified.
C) converged.
D) diverged.
E) inhibited.

Question 33

Within the meninges,cerebrospinal fluid occupies the

A) pia mater.
B) dura mater.
C) epidural space.
D) subarachnoid space.
E) none of the above.

Question 34

Which of the following is NOT a type of neuroglia?

A) astrocyte
B) oligodendrocyte
C) ependymal cell
D) neuron
E) microglial cell

Question 35

The pressure of cerebrospinal fluid is usually measured by introducing a hollow needle between lumbar vertebrae into the

A) dura mater.
B) pia mater.
C) arachnoid mater.
D) subarachnoid space.
E) none of these.

Question 36

In the central nervous system myelin is formed by

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

Question 37

The spinothalamic tract conducts impulses

A) from the thalamus to the cerebral cortex.
B) up the spinal cord to the thalamus.
C) down the spinal cord from the thalamus.
D) that stimulate contraction of skeletal muscle.
E) between left and right cerebral hemispheres.

Question 38

The part of the brain that coordinates voluntary muscle movements is the

A) cerebrum.
B) medulla oblongata.
C) cerebellum.
D) corpus callosum.
E) midbrain.

Question 39

The cellular processes of neurons that provide receptive surfaces for input from other neurons are

A) neurofibrils.
B) Nissl fibers.
C) axons.
D) dendrites.
E) nuclei.

Question 40

Which of the following lists parts of a reflex arc in the correct sequence?

A) receptor,motor neuron,sensory neuron,interneuron,effector
B) effector,receptor,sensory neuron,interneuron,motor neuron
C) effector,sensory neuron,receptor,motor neuron,interneuron
D) receptor,sensory neuron,interneuron.motor neuron,effector
E) receptor,interneuron,effector,sensory neuron,motor neuron

Question 41

These neuroglia form an epithelial-like membrane that lines the enclosed spaces of the brain and spinal cord.

A) astrocytes
B) ependymal cells
C) oligodendrocytes
D) microglia
E) Schwann cells

Question 42

These neuroglia form the insulating myelin sheath around axons of the central nervous system.

A) astrocytes
B) ependymal cells
C) oligodendrocytes
D) microglia
E) Schwann cells

Question 43

These neuroglia produce the myelin sheath on neurons of the peripheral nervous system.

A) astrocytes
B) ependymal cells
C) oligodendrocytes
D) microglia
E) Schwann cells

Question 44

The two major types of cells found in nervous tissue are

A) neurons and neuroglia.
B) dendrites and axions.
C) neurons and effectors.
D) astrocytes and Schwann cells.
E) neurons and nerves.

Question 45

Unmyelinated axons and neuron cell bodies form

A) gray matter.
B) white matter.
C) nodes of Ranvier.
D) chromatophilic substance.

Question 46

Gaps in the myelin sheath are called

A) gap junctions.
B) neurofibrils.
C) nodes of Ranvier.
D) synapses.

Question 47

These neuroglia provide structural support between neurons and blood vessels,have numerous processes,and help regulate extracellular nutrient and ion concentration.

A) astrocytes
B) ependymal cells
C) oligodendrocytes
D) microglia
E) Schwann cells

Question 48

This neuron process originates as a single structure but may give off many branches.

A) axon
B) dendrite
C) myelin sheath
D) soma

Question 49

When 10 or more pre-synaptic neurons conduct impulses to 5 or fewer post-synaptic neurons,the conduction pattern is said to be

A) divergent.
B) emergent.
C) hyperpolarizing.
D) convergent.

Question 50

The neurilemma

A) is the neuron's plasma membrane.
B) is the sarcolemma of the neuron.
C) surrounds the myelin sheath.
D) only surrounds the soma of the central nervous system neurons.

Question 51

A branch-like sensory process of a neuron that provides the main receptive surface for communication is called a(n)

A) Nissl substance.
B) axon.
C) neurilemma.
D) dendrite.

Question 52

Which of the following are adrenergic fibers?

A) parasympathetic postganglionic fibers
B) sympathetic postganglionic fibers
C) parasympathetic preganglionic fibers
D) sympathetic preganglionic fibers
E) motor fibers to skeletal muscle

Question 53

The cardiac and vasomotor centers are located in the

A) pons.
B) medulla oblongata.
C) cerebellum.
D) frontal lobe.
E) thalamus.

Question 54

These neuroglia are found in the central nervous system and phagocytize bacterial cells and cellular debris.

A) astrocytes
B) ependymal cells
C) oligodendrocytes
D) microglia
E) Schwann cells

Question 55

The respiratory areas are in the pons and in the

A) thalamus.
B) cerebrum.
C) midbrain.
D) medulla oblongata.
E) cerebellum.

Question 56

These convert environmental information into impulses that are conducted to the central nervous system.

A) sensory receptors
B) motor nerves
C) effectors
D) neuroglia
E) myelin

Question 57

Which of the following is a part of the diencephalon?

A) thalamus
B) cerebral aqueduct
C) cerebral peduncles
D) frontal lobe
E) pons

Question 58

This motor branch of the peripheral nervous system controls skeletal muscle.

A) visceral branch
B) autonomic branch
C) somatic branch
D) sensory branch
E) receptor branch

Question 59

The complex network of tiny islands of gray matter in the brain that "awakens" the cerebral cortex is the

A) dentate nucleus.
B) reticular formation.
C) limbic system.
D) corpora quadrigemina.
E) cerebellum.

Question 60

The phrenic nerves arise from the

A) cervical plexuses.
B) brachial plexuses.
C) lumbar plexuses.
D) sacral plexuses.
E) brainstem.

Question 61

When the measured potential of a membrane reaches threshold,

A) potassium rapidly enters the cell.
B) potassium rapidly leaves the cell.
C) sodium rapidly enters the cell.
D) sodium rapidly leaves the cell.

Question 62

Neurotransmitters that move the post-synaptic membrane potential closer to threshold are

A) inhibitory.
B) excitatory.
C) all-or-none.
D) hyperpolarizing.

Question 63

This structural type of neuron includes most neurons whose cell bodies lie within the central nervous system.

A) sensory neurons
B) multipolar
C) bipolar
D) unipolar

Question 64

This structural type of neuron has a single process that extends from the cell body.

A) unipolar
B) bipolar
C) multipolar

Question 65

In most neurons,the threshold potential is about

A) - 55 mV.
B) - 100 mV.
C) + 25 mV.
D) + 30 mV.

Question 66

When a neuron's membrane becomes more permeable to sodium,the neuron

A) becomes polarized.
B) hyperepolarizes.
C) depolarizes
D) repolarizes.

Question 67

A neuron's "trigger zone" is the

A) axon hillock.
B) axon terminal.
C) soma.
D) synaptic knob.

Question 68

Neurons entirely contained within the brain or spinal cord are functionally classified as

A) motor neurons
B) interneurons
C) sensory neurons

Question 69

Impulse conduction is ________ in myelinated nerve fibers.

A) faster
B) slower

Question 70

Neurons found only in specialized parts of the eyes,nose,and ears are

A) bipolar.
B) unipolar.
C) multipolar.
D) motor only.

Question 71

Which is NOT a method for clearing neurotransmitters from the synaptic cleft?

A) decomposition by enzymes
B) reuptake by the releasing neuron
C) diffusion away from the synapse
D) phagocytosis by dendritic cells

Question 72

When a neuron's plasma membrane becomes more permeable to potassium,

A) potassium leaves the cell.
B) potassium enters the cell.
C) sodium enters the cell.
D) sodium leaves the cell.

Question 73

This condition is caused by unequal distribution of positive and negative charges across the plasma membrane of a neuron.

A) neutralization
B) neurulation
C) polarization
D) potentiation

Question 74

Faster impulse conduction speeds are possible with _______ axons.

A) thin diameter
B) thick diameter

Question 75

When an impulse jumps from node to node along a myelinated axon,the conduction is termed

A) saltatory.
B) salutatory.
C) transitory.
D) sub-threshold.

Question 76

In a resting neuron,the difference in charges between the outside and inside of the membrane is called a(n)

A) action potential.
B) resting potential.
C) graded potential.
D) retrograde potential.

Question 77

Neurotransmitters that hyperpolarize post-synaptic membranes are always

A) inhibitory.
B) excitatory.
C) all-or-none.
D) acetylcholine.

Question 78

The most abundant cation within cells is ________;the most abundant cation outside of cells is ________.

A) oxygen;carbon
B) hydrogen;oxygen
C) sodium;potassium
D) potassium;sodium

Question 79

If a neuron's membrane potential measures +25mV,the neuron is

A) polarized.
B) hyperpolarized.
C) depolarized
D) repolarized.

Question 80

Neurons that conduct impulses into the brain or spinal cord are functionally classified as

A) motor neurons.
B) interneurons.
C) sensory neurons.