Neural Tissue- Chapter 12 Flashcards
Which part of the nervous system performs the higher-order thinking required to complete this practice exam?
peripheral nervous system
afferent division
autonomic nervous system
central nervous system
central nervous system
Think about how functioning changes as you travel to superior areas.
Which of the following structures is NOT part of the PNS?
a sensory receptor
a ganglion
an interneuron within the spinal cord
an interneuron within an autonomic ganglion
an interneuron within the spinal cord
What structures are away from the periphery?
What is included in the primary functions of the nervous system?
regulating and controlling peripheral structures and systems
integrating sensory information
providing sensation of the internal and external environments
All of the listed responses are correct.
All of the listed responses are correct.
Neurons are responsible for __________.
creating a three-dimensional framework for the CNS
controlling the interstitial environment
performing repairs in damaged neural tissue
information transfer and processing in the nervous system
information transfer and processing in the nervous system
The region of a neuron with voltage-gated sodium channels is the __________.
dendrite
perikaryon
soma
axon
axon
Remember this area propagates an action potential.
Neurons are classified on the basis of their structure as __________.
motor, sensory, association, or interneurons
efferent, afferent, association, or interneurons
anaxonic, unipolar, bipolar, or multipolar
astrocytes, oligodendrocytes, microglia, or ependymal
anaxonic, unipolar, bipolar, or multipolar
Remember the word that indicates an area of difference.
Neurons are classified on the basis of their function as __________.
motor, sensory, or association
somatic, visceral, or autonomic
unipolar, bipolar, or multipolar
central, peripheral, or somatic
motor, sensory, or association
Remember information is taken in and processed, and action is taken.
What are the two major cell populations of neural tissue?
astrocytes and oligodendrocytes
satellite cells and Schwann cells
neurons and neuroglia
microglia and ependymal cells
neurons and neuroglia
Which of the following CNS glial cells remove debris, wastes, and pathogens by phagocytosis?
ependymal cells
Schwann cells
microglia
astrocytes
microglia
Remember these cells have immune system functions.
The white matter of the CNS represents a region dominated by the presence of __________.
oligodendrocytes
astrocytes
neuroglia
unmyelinated axons
oligodendrocytes
These cells produce myelin.
Depolarization of the membrane will shift the membrane potential toward __________.
0 mV
–70 mV
–85 mV
–90 mV
0 mV
Remember the resting potential and how this changes.
What is the term given to describe a shift in transmembrane potential from –70 mV to –90 mV?
repolarization
hyperpolarization
depolarization
None of the listed responses is correct.
hyperpolarization
If resting membrane potential is –70 mV and the threshold is –60 mV, a membrane potential of –62 mV will __________.
produce an action potential
repolarize the membrane to −80 mV
depolarize the membrane to 0 mV
not produce an action potential
not produce an action potential
Remember the function of a threshold.
At the site of an action potential, the membrane contains __________.
an excess of negative ions inside and an excess of negative ions outside
an equal number of positive ions on either side of the membrane
an excess of positive ions inside and an excess of negative ions outside
an equal number of positive and negative ions on either side of the membrane
an excess of positive ions inside and an excess of negative ions outside
Remember this is the reverse of the resting membrane potential.
Which of the following statements about repolarization of an axon is FALSE?
Repolarization is marked by the movement of potassium ions out of the cell membrane.
During repolarization, the axon will be in a refractory period.
Repolarization occurs when sodium ion channels are open.
Repolarization follows depolarization of the axon.
Repolarization occurs when sodium ion channels are open.
Remember what happens during depolarization.
A node along the axon represents an area where __________.
there is an absence of myelin
there is a gap in the cell membrane
there is a layer of fat
there are interwoven layers of myelin and protein
there is an absence of myelin
Nerve cell bodies in the PNS are clustered together in masses called __________.
ganglia
neuromodulators
proprioceptors
nodes
ganglia
Satellite cells are also found here.
What are the most important factors that determine the rate of action potential conduction?
the presence or absence of a myelin sheath and the diameter of the axon
the number of neurons and the length of their axons
the strength of the stimulus and the rate at which the stimulus is applied
All of the listed responses are correct.
the presence or absence of a myelin sheath and the diameter of the axon
How does insulation factor in conduction?
At an electrical synapse, the presynaptic and postsynaptic membranes are locked together at __________.
gap junctions
myelinated axons
synaptic vesicles
neuromuscular junctions
gap junctions
Remember membranes from two cells are brought very close together here.
Exocytosis and the release of acetylcholine into the synaptic cleft are triggered by __________.
calcium ions flooding into the synaptic terminal
calcium ions leaving the cytoplasm
reabsorption of calcium into the endoplasmic reticulum
active transport of calcium into synaptic vesicles
calcium ions flooding into the synaptic terminal
Remember this is also needed for muscle contraction.
An important neurotransmitter in emotional states and moods is __________.
aspartate
acetylcholine
substance P
serotonin
serotonin
The drug Zoloft prevents this from being reabsorbed at axon terminals.
An excitatory postsynaptic potential (EPSP) is __________.
a graded depolarization produced by the arrival of a neurotransmitter
the same as a nerve impulse along an axon
an action potential complying with the all-or-none principle
a result of a stimulus strong enough to produce threshold
a graded depolarization produced by the arrival of a neurotransmitter
Remember what happens when sodium channels open.
An inhibitory postsynaptic potential (IPSP) is a __________.
depolarization produced by the effect of a neurotransmitter
repolarization produced by the addition of multiple stimuli
graded hyperpolarization of the postsynaptic membrane
reflection of the activation of an opposing transmembrane potential
graded hyperpolarization of the postsynaptic membrane
Remember this is an exaggeration of the existing membrane potential.
Rabies is a viral disease contracted from the bite of an infected animal. Rabies bypasses many immune system defenses by traveling in peripheral neurons to reach the CNS. Which method of transport is NOT used by the rabies virus to reach the CNS?
anterograde flow
axoplasmic transport
retrograde flow
osmosis
anterograde flow
Remember the virus needs to move toward the brain and spinal cord.
The reason that active neurons need ATP is to support __________.
the recovery from action potentials
the synthesis, release, and recycling of neurotransmitter molecules
the movement of materials to and from the soma via axoplasmic flow
All of the listed responses are correct.
All of the listed responses are correct.
What processes require ATP?
Sensory neurons are responsible for carrying impulses __________.
to the PNS
away from the CNS
from the CNS to the PNS
to the CNS
to the CNS
Remember you receive information through sensory neurons.
Interneurons, or association neurons, differ from sensory and motor neurons in their __________.
inability to generate action potentials
structural characteristics
exclusive location in the brain and spinal cord
functional capabilities
exclusive location in the brain and spinal cord
Remember these form networks in the nervous system.
Efferent pathways consist of axons that carry impulses __________.
toward the CNS
to the spinal cord and into the brain
away from the CNS
from the PNS to the CNS
away from the CNS
This is also known as a motor pathway.
Graded potentials that develop on the postsynaptic membrane in response to a neurotransmitter are __________.
postsynaptic potentials
presynaptic inhibitors
presynaptic potentials
presynaptic facilitators
postsynaptic potentials
Remember these can be summed to reach threshold potential.
The addition of stimuli occurring in rapid succession at a single synapse is __________.
the absolute refractory period
spatial summation
facilitation
temporal summation
temporal summation
Remember this has to do with timing.
What type of gated channel opens or closes in response to distortion of the membrane?
mechanically gated channel
chemically gated channel
voltage-gated channel
leak channel
mechanically gated channel
Remember this is how pressure receptors are activated.
Interneurons are responsible for __________.
carrying instructions from the CNS to peripheral effectors
analysis of sensory inputs and coordination of motor outputs
collecting information from the external or internal environment
delivery of information to the CNS
analysis of sensory inputs and coordination of motor outputs
Remember these neural cells form networks in the nervous system.
Sensory (ascending) pathways distribute information __________.
from peripheral receptors to processing centers in the brain
from the central nervous system to the peripheral nervous system
from motor pathways to interneurons in the CNS
from processing centers in the brain to peripheral receptors
from peripheral receptors to processing centers in the brain
Remember you receive information from the outside by this pathway.
Tyson decides to travel overseas but does not have all the required vaccines needed before he goes. While on his trip, he contracts diphtheria. Which type of glial cell is particularly at risk from this disease?
microglia
satellite cells
oligodendrocytes
Schwann cells
Schwann cells
Remember this type of cell produces myelin.
Schwann cells are glial cells responsible for __________.
surrounding nerve cell bodies in peripheral ganglia
secretion of cerebrospinal fluid
phagocytic activities in the neural tissue of the PNS
producing a neurilemma around peripheral axons
producing a neurilemma around peripheral axons
These cells produce myelin.
What happens when a barrier prevents the movement of opposite charges toward one another?
A generation potential is produced.
A current is produced.
An action potential occurs.
A potential difference exists.
A potential difference exists.
Remember this creates a voltage.
Which of the following statements about the sodium-potassium pump is correct?
The sodium-potassium pump requires ATP to pump sodium and potassium ions from higher to lower concentrations along their concentration gradients.
The sodium-potassium pump is a leak channel that allows passive movement of sodium and potassium ions down the concentration gradient.
The sodium-potassium pump brings sodium into a neuron during depolarization and forces potassium out of a neuron during depolarization.
The activity of the sodium-potassium pump is needed after every action potential to restore resting potential.
The activity of the sodium-potassium pump is needed after every action potential to restore resting potential.
Remember this helps distribute sodium back outside.
Which of the following is a correct statement of the all-or-nothing principle?
A hyperpolarized membrane always results in the production of an action potential.
When a stimulus is applied, it triggers an action potential in the membrane.
Action potentials occur in all neurons if a stimulus is applied that lowers the membrane potential.
A given stimulus either triggers a typical action potential or does not produce one at all.
A given stimulus either triggers a typical action potential or does not produce one at all.
During the relative refractory period, a larger-than-normal depolarizing stimulus can __________.
bring the membrane to threshold and initiate a second action potential
inhibit the production of an action potential
cause the membrane to hyperpolarize
cause a membrane to reject a response to further stimulation
bring the membrane to threshold and initiate a second action potential
Remember the difference between absolute and relative refractory periods.
Saltatory conduction conducts impulses along an axon __________.
five to seven times faster than continuous conduction
at a velocity determined by the rate at which the stimulus is applied
two to three times more slowly than continuous conduction
at a rate determined by the strength of the stimulus
five to seven times faster than continuous conduction
Remember the effect of myelin on conduction in axons.
In type C fibers, action potentials are conducted at speeds of approximately __________.
2 mph
40 mph
150 mph
500 mph
2 mph
Which of the following is true of axons?
The larger the diameter of the axon, the greater the resistance.
The larger the diameter of the axon, the slower the rate of transmission.
The size of the axon does not affect the rate of transmission or resistance.
The larger the diameter of the axon, the faster the rate of transmission
The larger the diameter of the axon, the faster the rate of transmission.
Remember this increases helps transfer information.
Facilitation in the neuron’s transmembrane potential toward threshold results from what?
exposure to certain drugs, such as nicotine
summation of EPSPs
any shift that makes the cell more sensitive to further stimulation
All of the listed responses are correct.
All of the listed responses are correct.
Think of the factors that help a membrane approach threshold.
Rachel decides to go swimming, but when she sticks her big toe into the water, she changes her mind because the water is too cold. The sensory neurons responsible for sending the message about the temperature of the cold water are __________.
enviroceptors
interoceptors
exteroceptors
proprioceptors
exteroceptors
The prefix for this word means “outside.”
The main functional difference between the autonomic nervous system and the somatic nervous system is that the activities of the ANS are __________.
primarily involuntary, or under
“
automatic
”
control
involved with affecting skeletal muscle activity
involved with carrying impulses to the CNS
primarily voluntary controlled
primarily involuntary, or under “automatic” control
Think about what the prefix “auto” means.
Lulu, who is 50 years old, decides she wants to receive Botox treatments. If Botox, short for botulism toxin, prevents the release of ACh from synaptic terminals, what effect should Lulu expect from having Botox injected into her facial muscles?
temporary paralysis in the injected facial muscles
difficulty breathing
prolonged muscle contractions in her facial muscles
None of the listed responses is correct.
temporary paralysis in the injected facial muscles
Remember Ach is needed for muscle contraction.
What happens when depolarization to threshold occurs?
Voltage-gated sodium channels are opened.
Voltage-gated potassium channels open.
Leak channels are activated.
Sodium channels are inactivated.
Voltage-gated sodium channels are opened.
Remember this involves gates that are triggered by changes in electrical potential.
Emma is very excited because after taking up running several months ago, she has begun to experience the phenomenon called “runner’s high.” This is caused by the production of endorphins. What is the effect of the endorphins on Emma when she runs?
Endorphins lower the level of threshold at the initial segments of her axons, making it easier for impulses to be transmitted through her body.
Endorphins are blocking the transmission of substance P, a neurotransmitter that sends information about pain to the CNS.
Endorphins cause an increase in the amount of myelin on axons, making impulses travel faster.
None of the listed responses is correct.
Endorphins are blocking the transmission of substance P, a neurotransmitter that sends information about pain to the CNS.
Remember endorphins are neuromodulators.
Which of the following is the most excitatory neurotransmitter in the brain and functions in learning and memory?
norepinephrine
anamidine
dynorphins
glutamate
glutamate
Remember this is derived from an amino acid.
Ann and Elise are two college students on an overseas vacation. Because they both love seafood, they stop at a restaurant in a coastal town for lunch. After dining on shellfish, they become very sick and have trouble breathing. What may have happened to Ann and Elise?
They may have consumed ciguatoxin (CTX), which can interfere with muscle control.
They may have consumed some tetrodotoxin (TTX), which can cause abnormal sensations.
They may have consumed saxitoxin (STX), which blocks sodium ion channels.
Any of the responses could be correct. TTX, STX, and CTX all block sodium ion channels, cause abnormal sensations, and interfere with muscle control.
Any of the responses could be correct. TTX, STX, and CTX all block sodium ion channels, cause abnormal sensations, and interfere with muscle control.
What is the general effect of neurotoxins?
