Which cells in the nervous system do most of the work of receiving, integrating, and transmitting information?
neurons
glial cells
axons
dendrites
Which of the following is the most accurate description of the structure and function of all neurons in your central nervous system?
All neurons contain a cell body and an axon, and may have other structures.
All neurons receive information via one or more dendrites and send information via one or more axons.
All neurons synapse onto another neuron in order to transmit an electrical signal.
All neurons receive and send information.
Which of the following is NOT one of the main functions of neurons?
integrating information
generating information
transmitting information
receiving information
What are three basic components of most neurons?
vesicles, terminal buttons, synapses
myelin, nodes, axon terminals
cell body, axon, dendrites
hindbrain, midbrain, forebrain
Which neuronal structures are analogous to branches on a tree?
nuclei
cell bodies
On a typical neuron, which structure receives neurochemical information, and which structure sends neurochemical information to other neurons?
Dendrites receive; axons send.
Axons send; synapses receive.
Dendrites receive; synapses send.
Axons receive; dendrites send.
In computers, the keyboard is the component of the computer that receives information. What would the keyboard be equivalent to, in comparing a computer to a neuron?
axon
soma
dendrite
terminal button
Emma has a disorder that includes degeneration of myelin sheaths in her nervous system. Which of the following disorders does Emma most likely have?
Alzheimer’s disease
multiple sclerosis
Broca’s aphasia
Parkinson’s disease
Which of the following is associated with the fastest neural impulses?
unmyelinated dendrites
myelinated axons
shorter axons
multiple dendrites
When you want to print something from a computer, a cable carries this signal from the computer to the printer. In comparing a computer and printer to two neurons, what is the neuronal equivalent to the cable?
synapse
When you are printing something from your computer, your cable must be securely connected to the printer or else the signal won’t get through. If you compared a computer and printer to two neurons, what is the neuronal equivalent of the connection between the cable and the printer?
Which part of the neuron secretes neurotransmitters?
neuromodulators
myelin sheaths
terminal buttons
Which of the following is the correct sequence of structures through which information flows in a neuron?
dendrites to axon to soma
axon to glia to dendrites
glia to dendrites to axon
dendrites to soma to axon
What are the cells that provide structural support and insulation for neurons?
synapses
sheaths
glia
What is the primary role of glial cells?
They form the primary components of the spinal cord.
They provide support for neurons.
They release neurotransmitters.
They release neuromodulators.
What would happen if you were to lose all of your glial cells?
There would be no change in functioning, because neurons are the cells that are important for transmission of information within the nervous system.
One hemisphere could not send information to the other hemisphere.
Your neurons would no longer have a normal chemical environment, and there would be problems with efficient neurotransmission.
You would no longer be able to send neurotransmitters from one cell to another.
Which of the following is a characteristic of both sodium and potassium ions?
They carry a negative charge.
They are concentrated inside the neuron’s cell body.
They carry a positive charge.
They are capable of changing their potentials.
What do we call the tiny electrical charge that exists when a neuron is neither receiving nor sending information?
resting potential
action potential
post-synaptic potential
inhibitory potential
When a neuron is neither receiving nor sending, what is the approximate voltage of the electrical charge that exists between the inside and the outside of a neuron?
–700 millivolts
–70 millivolts
+70 millivolts
+700 millivolts
Bradley is deeply relaxed and many of his muscles are not moving at all. What does this suggest about many of Bradley’s motor neurons?
They have a voltage of +70 millivolts.
They have a voltage of –70 millivolts.
They are in a relative refractory period.
They are in an absolute refractory period.
When the sodium channels of a neuron open, allowing sodium ions to flow inside, which of the following is most likely to happen next?
a resting potential
an action potential
a refractory period
reuptake
What is an action potential?
an electrical signal that travels along the axon of a neuron
the small gap that exists between adjacent neurons
the tiny electrical charge that exists when a neuron is neither receiving nor sending information
the release of neurotransmitters
Tracey became dehydrated during a recent illness, and the levels of sodium in her body were significantly reduced. What would we expect to occur if enough sodium was lost?
Her nervous system would become highly activated, and action potentials would be generated continuously.
More neurotransmitters would be produced in her terminal buttons.
Fewer action potentials would occur in her nervous system.
Glial cells would start to degenerate and die.
A neuron just sent a neural impulse. It will be one to two milliseconds before another neural impulse can be generated. What do we call this brief time increment, when another neural impulse cannot occur?
absolute refractory period
postsynaptic discharge
all-or-none period
What is the term for the minimum length of time between action potentials?
relative threshold period
transduction interval
synaptic interval
Which of the following is known about action potentials?
They travel more slowly if the incoming stimulation is less intense.
They are stronger when the incoming stimulation is more intense.
They are generated in an all-or-none fashion.
They are seldom strong enough to reach the terminal buttons.
What is the typical speed of an action potential?
at least 600 kilometres/hour
up to 300 kilometres/hour
approximately the speed of light (300,000 kilometres/second)
approximately the speed of sound (1236 kilometres/hour)
Sara is holding Scott’s hand during a scary movie. Suddenly she squeezes his hand very hard. When she does this, what will the nerves in Scott’s hand do?
release more GABA
send larger action potentials to his central nervous system
enter an absolute refractory period
start to fire at a faster rate
Fiona puts her hands into a bucket of lukewarm water; Luke puts his hands into a bucket of ice-cold water. What should we predict about each of their action potentials?
Only Fiona will experience enough stimulation to trigger an action potential.
Luke will have inhibitory action potentials.
Their action potentials will differ in rate, due to differences in the intensity of the stimuli.
Their action potentials will differ in size, due to differences in the intensity of the stimuli.
Peggy smells a very strong odour; Harry smells an odour that is barely detectable. Based on what is known about neural transmission, what should we predict about each of their action potentials?
They will be the same size but at different rates.
Peggy’s will be excitatory, and Harry’s will be inhibitory.
They will be weaker in Harry’s system because the stimulus is less intense.
They will be distinguished by the amount of inhibition they exert on synapses.
What do we call the space between a terminal button and a dendrite?
the transmission gap
the midsynaptic potential range
the synaptic cleft
the neuromodulator
Where are neurotransmitters stored?
in the dendrites
in the mitochondria
in the axon
in the synaptic vesicles
What do synaptic vesicles do?
They fuse with the postsynaptic cell.
They store neurotransmitters.
They block receptors.
They manufacture myelin.
What happens when a neurotransmitter is released from a presynaptic neuron, but it does not fit into a suitable receptor channel on the postsynaptic neuron?
The firing potential of the postsynaptic neuron will not be affected.
An inhibitory postsynaptic potential will be generated.
A graded potential will be generated.
The presynaptic neuron will be inhibited.
What is a good analogy for the way in which a neurotransmitter binds to receptor sites?
the lowering of a drawbridge
a key fitting in a lock
the pulling of a gun trigger
the opening and closing of a window
What type of electric potential increases the likelihood that the postsynaptic neuron will fire?
all-or-none potential
excitatory postsynaptic potential
inhibitory postsynaptic potential
The voltage at a receptor site has just changed from –70 millivolts to –75 millivolts. What caused the change?
influx of potassium ions
influx of sodium ions
The voltage at a receptor site has just changed from –70 millivolts to –67 millivolts. What will this lead to?
an absolute refractory period
increased likelihood of an action potential
decreased likelihood of an action potential
a relative refractory period
What do we call the process of absorption of neurotransmitters into the presynaptic neuron?
neurotransmission
graded potential
inhibition
Which of the following is the correct sequence of steps through which neurotransmitters progress during synaptic transmission?
binding, synthesis, release, inactivation, reuptake
synthesis, release, binding, inactivation, reuptake
synthesis, binding, release, reuptake, inactivation
release, synthesis, binding, reuptake, inactivation
If a brain has several synapses that are not particularly active, those synapses may be eliminated. What is this process called?
synaptic pruning
natural selection
long-term potentiation
At what age do humans tend to have the largest number of synapses?
at birth
at 1 year
at puberty
after physical growth has ended in early adulthood
According to the Hebbian Learning Rule, if an axon of Cell A is near enough to repeatedly stimulate Cell B (causing it to fire often), then what will happen to Cell B?
Cell B will eventually stop responding to Cell A.
Cell B will merge with Cell A.
Cell B will be pruned because it is redundant with Cell A.
Cell B will become more likely to fire in response to signals from Cell A.
Which of the following neurotransmitters is primarily involved in the activation of motor neurons controlling skeletal muscles?
GABA
acetylcholine
serotonin
norepinephrine
Jeremy is sitting quietly when the voluntary muscles in his left leg begin to twitch. Which neurotransmitter is likely being released?
When your text states that nicotine functions as an acetylcholine agonist, what does that mean?
It interacts with acetylcholine to produce a novel effect.
It occupies acetylcholine receptor sites, thus blocking the action of the neurotransmitter.
It stimulates some acetylcholine synapses.
It inhibits some acetylcholine release.
What does an agonist do?
It extends the absolute refractory period of neural transmission.
It blocks the action of neurotransmitters.
It mimics the action of a neurotransmitter.
It prevents reuptake of neurotransmitters.
Curare blocks the action of acetylcholine by occupying its receptor sites. In this context, what is curare?
a neurotransmitter
an agonist
a neuromodulator
an antagonist
Dr. Jacoby has just discovered a new drug named Z2W that is an antagonist to acetylcholine. What are some likely side effects of this new drug?
hallucinations and disrupted sleep patterns
general stimulation within the body and an increase in heart rate
sleepiness and loss of interest in activities
motor and memory problems
Dr. Ferracane has just discovered a new drug named GL8 that produces side effects such as paralysis and memory loss. Based on this information, how might this drug act on the nervous system?
as an agonist for GABA
as an antagonist for GABA
as an antagonist for acetylcholine
as an agonist for acetylcholine
What seems to be a primary cause of Parkinson’s disease?
degeneration of neurons that use dopamine as a neurotransmitter
degeneration of myelin sheaths
antagonistic effects on acetylcholine receptors
damage to glial cells
Garrett has a chronic disease that is slowly destroying the cells that produce serotonin in his brain. Which of the following will likely happen to Garrett as his disease progresses?
His memory will gradually worsen.
He will start to show signs of Parkinson’s disease.
His sleep and mood will be disrupted.
He will begin to experience symptoms of schizophrenia.
Which of the following disorders is associated with reduced activity at norepinephrine and serotonin receptors?
depression
schizophrenia
Julia is currently in the midst of a major depression. Which of the following patterns of neurotransmitter activity is most likely to be associated with her symptoms?
reduced levels of GABA
increased activity at serotonin synapses
increased levels of dopamine
reduced activity at norepinephrine synapses
Stuart abuses a drug that is a dopamine agonist. Which of the following is Stuart most likely to experience when he is high?
deep relaxation
hallucinations
temporary paralysis
excessive anxiety
Caitlin has taken a drug that has reduced the levels of GABA in her nervous system. What side effect is Caitlin likely to experience?
motor tics and other involuntary motor movements
increased levels of anxiety
Dr. Athorp has just discovered a new drug named P3X that is an agonist for GABA. What effects will this drug likely have?
a reduction in pain and a sense of euphoria
anxiety reduction and general relaxation
Which of the following neurotransmitters always has inhibitory effects?
glutamate
Which of the following neurotransmitters has effects on learning and memory, and on long-term potentiation?
Opiate drugs bind onto the same receptor sites as the body’s own endorphins. What effect, then, do opiate drugs have?
They increase anxiety and agitation.
They inhibit visual sensations.
They produce insomnia.
They relieve pain.
Which of the following neurotransmitters is most similar to the drug heroin?
dopamine
endorphins
If you were making a new drug to treat pain, which type of neurotransmitter would you attempt to mimic?
monoamines
