lab 10 practice test

Question 1

a drug that functions as an agonist

Answer 1

activates a receptor, helping a neurotransmitter bind or triggering an an action potential in some other way

Question 2

muscles and glands that respond to nerve impulses are called

Answer 2

effectors

Question 3

most of the neurons in the brain and spinal cord are

Answer 3

multipolar

Question 4

which of the following neuroglia is not part of the CNS

Answer 4

satellite cells

Question 5

neurons that convey impulses from the CNS to muscles or glands are

Answer 5

none of the above

Question 6

which of the following ions cross cell membranes most readily

Answer 6

potassium

Question 7

in order for a severed peripheral nerve to regenerate and recover its original function, nerve fibers must sprout and enter tubes formed by

Answer 7

basement membranes and connective tissues

Question 8

the space between neurons is called the neuronal space

Answer 8

false

Question 9

the difference in electrical charge between the inside and outside of a polarized neuron cell membrane is called the

Answer 9

resting potential

Question 10

a nerve impulse consists of a wave of ___ moving away from a point of stimulation

Answer 10

action potentials

Question 11

the cytoplasmic extensions that, together with the cell body, provide the main receptive surfaces for neurons are

Answer 11

dendrites

Question 12

drugs that decrease membrane permeability to sodium

Answer 12

all of the above

Question 13

during the absolute refractory period, a stimulus of high intensity may trigger a nerve impulse

Answer 13

false

Question 14

which of the following is unique to neurons

Answer 14

chromatophilic substance

Question 15

interneurons are specialized to carry impulses from receptor cells into the brain or spinal cord

Answer 15

false

Question 16

diverging axons amplify an impulse by

Answer 16

contacting many neurons

Question 17

a ___ is the junction between neurons

Answer 17

synapse

Question 18

every neuron has

Answer 18

a cell body

Question 19

an excitatory postsynaptic potential lasts for about

Answer 19

15 milliseconds

Question 20

astrocytes structurally support neurons and also provide important signals and nutrients to neurons

Answer 20

true

Question 21

myelin is composed largely of carbohydrates

Answer 21

false

Question 22

the nervous system

Answer 22

all of the above

Question 23

neurotransmitters that affect a neuron’s response to other neurotransmitters are called

Answer 23

neuromodulators

Question 24

opiate drugs derived from poppies relieve pain in humans because the human nervous system has

Answer 24

receptors for endogenous opiates

Question 25

a nerve is a single neuron that transmits nerve impulses

Answer 25

false

Question 26

an action potential is triggered if

Answer 26

EPSPs overpower IPSPs

Question 27

presynaptic neurons release neurotransmitters by

Answer 27

exocytosis

Question 28

synaptic knobs are at the ends of

Answer 28

axons

Question 29

drugs that increase the actions of norepinephrine and/or serotonin by keeping them in synapses longer are most likely used to treat

Answer 29

clinical depression

Question 30

transmitting a nerve impulse from one neuron to another involves a

Answer 30

nerve impulse stimulating a presynaptic axon to release a neurotransmitter into a synaptic cleft

Question 31

which of the following molecules is responsible for "runner's high," a good feeling that accompanies long-distance running

Answer 31

beta endorphin

Question 32

clusters of neuron cell bodies are called

Answer 32

ganglia

Question 33

migraine results from

Answer 33

release of calcitonin gene-related peptide from the trigeminal nerves at the base of the brain, in response to a spreading wave of excitation followed by lack of response from the cortex

Question 34

multiple sclerosis is caused by an abnormal response of the

Answer 34

immune system

Question 35

what is the correct sequence of events that follows a threshold potential?

Answer 35

2,1,4,3

Question 36

which of the following cells is only found in the PNS

Answer 36

schwann cells

Question 37

convergence refers to

Answer 37

axons from neurons in different parts of the nervous system contacting the same neuron

Question 38

the cells in the nervous system that fill spaces and support neurons both physically and nutritionally are called

Answer 38

neuroglia

Question 39

if a neurotransmitter hyperpolarizes a cell membrane and an action potential is less likely, the change is called

Answer 39

inhibitory postsynaptic potential

Question 40

several nerve fibers converging onto one nerve fiber amplifies nerve impulses

Answer 40

false

Question 41

a reason that the CNS and PNS differ in their ability to regenerate after injury is that

Answer 41

axons of the CNS lack neurilemmae

Question 42

a mixed nerve includes different neuroglial cells

Answer 42

false

Question 43

in convergence, two or more incoming fibers contact a single neuron, whereas in divergence, impulses leaving a neuron pass into several output fibers

Answer 43

true

Question 44

each neuron in the CNS receives input from

Answer 44

thousands of axons

Question 45

myelin is rich in

Answer 45

lipids

Question 46

the most rapid nerve impulses are conducted on fibers that are

Answer 46

thick and myelinated

Question 47

a series of similar stimuli that increases change in local membrane potential is called

Answer 47

summation

Question 48

which of the following is (are) a type of neuroglia

Answer 48

all of the above

Question 49

sensory receptors are part of the CNS

Answer 49

false

Question 50

Marjorie takes an anti-anxiety drug so that she can sleep better and remain calm enough to study effectively. She begins by taking 25 milligrams every evening, but within a month, this does is no longer helping, so she takes two pills. After another month, this dosage is no longer effective. This is happening because

Answer 50

the number of receptors to which the drug binds on neurons has declined

Question 51

an immune response that triggers inflammation of the spinal cord and brain, leaving scars is

Answer 51

multiple sclerosis

Question 52

the neurotransmitter that controls skeletal muscle contraction is

Answer 52

acetylcholine

Question 53

during an action potential, calcium ions cause

Answer 53

sodium channels to close

Question 54

enkephalins are neuropeptides

Answer 54

true

Question 55

masses of myelinated nerve fibers appear

Answer 55

white

Question 56

converging nerve fibers amplify nerve impulses

Answer 56

false

Question 57

a nerve cell membrane may become depolarized as a result of

Answer 57

some ion channels being opened while others are closed

Question 58

___ support the axon from within

Answer 58

neurofibrils

Question 59

when a nerve fiber is polarized, the concentration of

Answer 59

Na+ is higher on the outside of the membrane and K+ is higher on the inside

Question 60

neural stem cells can be harvested from autopsies and stored, alive, in banks, whereas neurons cannot, because

Answer 60

neural stem cells have lower oxygen and energy requirements than neurons

Question 61

the space between neurons is a

Answer 61

synapse

Question 62

a neuron may have

Answer 62

one axon and many dendrites

Question 63

when an action potential passes over the surface of a synaptic knob, the contents of the vesicles are released in response to the presence of

Answer 63

calcium ions

Question 64

action potentials are related to nerve impulses in that

Answer 64

propagation of action potentials along a fiber constitutes a nerve impulse

Question 65

because the response of a nerve fiber is all-or-none, a greater intensity of stimulus does not produce a stronger impulse

Answer 65

true

Question 66

axon branches are called collaterals

Answer 66

true

Question 67

in reuptake

Answer 67

a neurotransmitter that has already been released into the synaptic cleft is taken back into the synaptic knob of the presynaptic neuron or into nearby neuroglia or neurons

Question 68

the two types of cells of the nervous system are

Answer 68

neurons and neuroglia

Question 69

three general functions of the nervous system are

Answer 69

integrative, motor, and sensory

Question 70

nodes of ranvier lie between neurons

Answer 70

false

Question 71

the somatic nervous system controls voluntary actions and the autonomic nervous system oversees involuntary actions

Answer 71

true

Question 72

neurotransmitters that are modified amino acids are

Answer 72

aspartic acid, glutamic acid, glycine, and GABA

Question 73

a stimulus great enough to change the membrane potential and propagate an action potential is said to have reached ____

Answer 73

threshold

Question 74

a myelinated nerve fiber is ___, whereas an unmyelinated nerve fiber is ____

Answer 74

white, and composing the white matter of the brain and spinal cord; gray, and composing the gray matter of the brain and spinal cord

Question 75

if a neuron receives a series of stimuli whose effect is excitatory but subthreshold, the neuron is more excitable to incoming stimulation than before and is said to be

Answer 75

facilitated

Question 76

neuroglia are specialized to react to environmental change, and neurons support neuroglia

Answer 76

false

Question 77

sensory receptors

Answer 77

all of the above

Question 78

if a resting potential becomes more negative, the membrane is

Answer 78

hyperpolarizing

Question 79

sheaths of ___ cells often enclose the larger axons outside of the brain and spinal cord

Answer 79

schwann

Question 80

drugs that inhibit the enzyme monoamine oxidase

Answer 80

allow increased activity of norepinephrine

Question 81

the types of neurons that are organized into neuronal pools are

Answer 81

interneurons

Question 82

dendrites on unipolar neurons are part of

Answer 82

sensory neurons

Question 83

which cells produce myelin in the brain and spinal cord

Answer 83

oligodendrocytes

Question 84

myelin

Answer 84

comprises much of the cell membrane of schwann cells

Question 85

the brain and spinal cord comprise the central nervous system

Answer 85

true

Question 86

saltatory conduction

Answer 86

is faster than conduction on an unmyelinated fiber

Question 87

the neurotransmitter most likely produced when a person uses a drug that creates a sense of well-being is

Answer 87

dopamine