biopsychology quizzes

In the experiments conducted by Hodgkin and Huxley, the early current disappeared if the membrane was clamped at _______ mV.

+52

Which observation was not observed in Hodgkin and colleagues' voltage-clamp study of squid action potentials?

A sustained outward current as a result of hyperpolarization

Which treatment would prevent the release of neurotransmitter from the presynaptic terminal?

A toxin that cleaves synaptobrevin

Which statement is a common, defining feature of membrane-bound active ion transporters?

All are able to move at least one ion against its concentration gradient

Based on the distribution of endocannabinoid receptors in the brain, it can be surmised that Δ9-tetrahydrocannabinol likely has an influence on

All of the above

Based on the observations made by Hodgkin and Huxley, one can expect ion channels to

All of the above

Cognitive neuroscience is concerned with

All of the above

Glutamate is

All of the above

In addition to their traditional motor program selection and implementation functions, the basal ganglia are also thought to be involved in

All of the above

In the operation of sodium-potassium ATPase,

All of the above

Tyrosine hydroxylase is a substrate for which protein kinase(s)?

All of the above

Which characteristic is an accepted criterion for classifying a molecule as a neurotransmitter?

All of the above

Which brain region is deactivated when a mother views a picture of her child?

Amygdala

Which statement best describes the action potential?

An action potential occurs when the cell's membrane potential reaches threshold

Which of the following is a characteristic of Purkinje cells that allows for the high level of convergence and divergence from the granule cells?

An elaborate dendritic tree that extends perpendicularly to the parallel fibers

Which of the following is a major function of the cerebellum?

Analyze errors between intended motor output and actual motor output

Which amygdaloid nucleus is correctly paired with its primary connections?

Central nucleus—hypothalamus

A scientist creates a D1 receptor knockout mouse. How would this effect the functioning of the basal ganglia?

Cerebral cortex input to spiny neurons would not be enhanced

Which of the following is the first step in the nuclear signaling process?

Chromatin decondensation

When a GABAA ionotropic receptor is stimulated by GABA in a developing neuron, which ions flow through its channel, and what effect does this have on the postsynaptic cell?

Cl-, which depolarizes the postsynaptic cell

Which protein plays a key role in endocytosis?

Clathrin

Which synapses have the strongest excitatory connection?

Climbing fibers synapsing on Purkinje cells

Which drug of abuse exerts its effect by interacting directly with dopamine synapses in the nucleus accumbens?

Cocaine

What would occur if the ATPase pumps in a neuron stopped functioning?

Concentration gradients would not be maintained across the membrane

Which structure can be found exclusively at an electrical synapse?

Connexon

Aromatase is responsible for which action?

Converts testosterone to estradiol

Which second messenger plays an important role in sensory transduction processes?

Cyclic nucleotide

Which technique first produced unequivocal support for the neuron doctrine of the nervous system (as opposed to the reticular theory)?

Electron microscopy of nervous tissue

Which of the following is not a class of opioid peptides?

Endocannabinoids

Which substance is not involved in masculinization of the genitalia and nervous system?

Epinephrine

Treating a male zebra finch during development with which drug would lead to a female-like neural song circuit?

Estrogen receptor antagonist

Which experimental model did Hodgkin and Katz use in their studies of the resting membrane potential?

Living squid neuron

The cell bodies of neurons that release norepinephrine project from which structure?

Locus coeruleus

Which statement about voltage-gated ion channels is true?

Na+ and K+ channels can work independently of one another

Which statement describes one of the features of Hodgkin and Huxley's mathematical model?

The action potential can be reconstructed based entirely on the time course and amplitudes of the ionic conductances

Refer to the figure. Which of the following is the key event at a membrane potential of -26 mV?

The late outward current increases in magnitude

Which statement about sexual dimorphism of the spinal nucleus of the bulbocavernosus (SNB) in rats is false?

The male perineal muscles have androgen receptors, but the female muscles do not.

Which current corresponds to a flow of Na+ in response to a depolarizing stimulus in a giant axon of a squid?

Transient inward current

Which gene regulation strategy underlies the action of glucocorticoid hormones?

Translocation of the receptor into the nucleus to bind to DNA

Which function is a characteristic primarily of neurons only, and not glia?

Transmits action potentials

What effect would testosterone treatment during development have on the size of the adult AVPV?

Treated females would have decreased cell numbers compared to control females due to an increase in apoptosis

What effect would testosterone treatment during development have on the size of the adult SDN-POA?

Treated females would have increased cell numbers compared to control females due to inhibition of apoptosis

Why is the white matter lighter than the gray matter?

White matter is richer in myelin, which reflects more light than gray matter

Under which circumstances is the Goldman equation equivalent to the Nernst equation?

When a membrane is permeable to only one ion

Which signaling pathway does not directly involve calcium?

cGMP

The axons transmitting cortical signals to the basal ganglia

carry information whose nature is poorly understood

Increased activity from the _______ to the subthalamic nucleus increases the _______ input to the VA/VL complex of the thalamus.

cerebral cortex; inhibitory

The acetylcholine receptor at the neuromuscular junction would best be described as a(n)

channel-linked receptor

The primary motor cortex processes information for muscles on the _______ side of the body; the cerebellum processes information for muscles on _______ side(s) of the body.

contralateral; the ipsilateral

One of the outputs of the basal ganglia, the substantia nigra pars reticulata, is most similar in its function to the

globus pallidus

There is a high degree of convergence from the medium spiny neurons to the neurons of the _______ and _______.

globus pallidus; substantia nigra pars reticulata

The TRP ion channel family includes channels responsive to

heat and cold

Injury to the fornix would prevent neural communication from the _______ to the _______.

hippocampus; hypothalamus

Neuroethology is the field devoted to studying complex behavior

in the native environment

Functional neuroimaging studies (Drevets and Raichle) of subjects with unipolar depression have shown

increased blood flow in the amygdala and specific areas in the prefrontal cortex

In deep brain stimulation for the treatment of Parkinson's disease,

stimulation parameters such as pulse width, current amplitudes, and pattern are determined by trial and error

In Parkinson's disease, dopaminergic input from the _______ decreases.

substantia nigra pars compacta

The external segment of the globus pallidus projects to the internal segment and the _______ in the _______ pathway.

subthalamic nucleus; indirect

Substania nigra pars reticulata axons project to _______; the globus pallidus axons do not project to this region.

superior colliculus

The substantia nigra pars reticulata projects to the

superior colliculus

What is the functional result of long-term depression in the cerebellum?

A stronger neuronal response of the deep excitatory loop

How many connexin subunits form one complete synaptic channel?

12

Listed below are the enzymes needed to synthesize epinephrine (adrenaline).1. Dopamine-β hydroxylase2. Tyrosine hydroxylase3. Phenylethanolamine-N-methyl transferase4. DOPA decarboxylaseWhich of the following is the correct sequence of enzyme actions in the synthesis of epinephrine?

2; 4; 1; 3

Listed below are the individual events that make up chemical synaptic transmission.1. Diffusion of transmitter across the synaptic cleft2. Depolarization of the presynaptic terminal3. Vesicle fusion with plasma membrane4. Opening of voltage-gated ion channels5. Activation of presynaptic, calcium-sensitive proteinsWhich sequence represents the correct ordering of these events?

2; 4; 5; 3; 1

Listed below are the events that make up NGF-mediated growth of sensory neurons.1. TrkA receptor self-phosphorylation2. Translocation of activated kinases to the nucleus3. NGF-induced dimerization of membrane receptors4. TrkA induction of the ras signaling pathwayWhich is the correct sequence of these events?

3; 1; 4; 2

Listed below are the events that occur during basal ganglia functioning.1. Disinhibition of ventral anterior and ventral lateral thalamic nuclei2. Inhibition of globus pallidus3. Excitation of caudate and putamenWhich of the following is the correct sequence of these events?

3; 2; 1

At which time interval between pre- and postsynaptic activity would STDP occur?

40 ms, regardless of whether pre- or postsynaptic activity occurs first

Refer to the figure. A researcher conducts a voltage clamp experiment on a giant squid axon. She clamps a typical neuron at 0mV. Which graph represents the current changes she will observe.

A

You are examining long-term potentiation in two groups of hippocampal neurons: control and treated. You induce lasting LTP in the control cells after repetitive high-frequency stimulation. In the treated cell, however, the potentiation begins to decrease after 2 hours. What treatment was given?

A drug that inhibits protein synthesis

Which statement describes a possible outcome for a neurotransmitter after release into the synaptic cleft?

Activation of G-protein-coupled receptor on postsynaptic cell

In a signal transduction cascade using G-proteins and cAMP, which is not a signal amplification step?

Activation of adenylyl cyclase molecules by G-proteins

Work done by _______ elucidated changes in membrane permeability that underlie an action potential.

Alan Hodgkin and Andrew Huxley

Which property of LTP underlies Pavlovian conditioning?

Associativity

Refer to the figure. Which region is responsible for communication between the hippocampus and the hypothalamus?

B

Which structure does not provide input to the amygdala?

Basal ganglia

Which feature of an electrical synapse allows synchronizing the electrical activity of multiple neurons?

Bidirectional transmission of electrical signals

The basal ganglia's ability to evoke one specific movement pattern out of an almost endless variety of possible movement patterns is best ascribed to which neural coding strategy?

Center-surround style decision making

What causes synaptic facilitation?

Buildup of Ca2+ in the presynaptic terminal

By which proposed molecular mechanism does Ca2+ promote fusion of synaptic vesicles?

By binding to and inducing changes in synaptotagmin that cause the plasma membrane to curve, facilitating fusion

Which protein facilitates the late phase of LTP?

CREB

Which statement about the mechanisms underlying hippocampal LTP induction is false?

Calcium decreases a resting leak current of sodium so that the postsynaptic cell is closer to threshold and therefore fires more easily

Refer to the figure. Which technique is illustrated in the figure, and what can it be used to measure?

Cell-attached patch clamp; measures the current that flows through a single ion channel

From which part of the nervous system do cells that innervate neuromuscular junctions originate?

Central nervous system (CNS)

A researcher injects a GABA antagonist into the globus pallidus and then stimulates the striatum. What are the expected changes in the downstream response?

Decreased activation of the globus pallidus and decreased excitation of the motor cortex

Which symptoms, together, indicate clinical depression?

Deep sadness, disordered sleep and eating, and poor concentration

Which of the following was observed in studies measuring the efflux of radioactive sodium from the squid giant axon?

Dependence of efflux upon the presence of ATP

A patient can smile when asked to by her doctor, but when she is told a funny joke, she is unable to smile. Where does the patient most likely have damage?

Descending projections from the hypothalamus

Which of Camillo Golgi's contributions enabled Santiago Ramón y Cajal to make observations that suggested that nerve cells are discrete entities?

Development of a staining method based on impregnation with silver salts

What is the direct role of the SRY gene?

Development of the testes

A scientist wishes to develop a new drug that prevents synaptic communication via neuropeptides but not small molecule neurotransmitters. Which mechanism would be a good target for his drug?

Disruption of axonal transport

Which neurotransmitter has been identified as seminally involved in an organism's reward system and is often altered by drugs of abuse?

Dopamine

Which would be the most likely consequence of a mutation that renders DOPA decarboxylase inactive?

Dopamine would not be produced

Which Drosophila melanogaster genotype is associated with the worst performance in an olfactory learning task?

Dunce, rutabaga double mutant

Damage to the midline of the cerebellar cortex would lead to dysfunction in what type of motor output?

Eye movement

What is the source of the quanta that make up the EPP?

Fusion of individual synaptic vesicles with the plasma membrane

The transmitter for the medium spiny neurons of the striatum is

GABA

Which receptor type can be modulated by both barbiturates and benzodiazepines?

GABAA

Refer to the figure. Which region of the basal ganglia is indicated by the asterisk?

Globus pallidus

Output from the basal ganglia projects from which structures?

Globus pallidus and substantia nigra pars reticulata

Subthalamic nucleus neurons that project to the internal segment of the globus pallidus release which transmitter?

Glutamate

What is the main excitatory neurotransmitter in the adult brain?

Glutamate

The presence of which compound or protein in a cell makes it quite likely that the cell is a GABAergic neuron?

Glutamic acid decarboxylase

Damage to the subthalamic nucleus results in which condition?

Hemiballismus

A female rodent is treated with dihydrotestosterone (DHT) during development. DHT acts on androgen receptors and is not converted to estradiol. Which outcome would you expect to see?

Her SDN-POA would be the same size as control females

A male student participated in a genetic testing experiment at his university. He discovered that he is genetically XX. How could this be?

His second X chromosome was completely inactivated, leading to the default male phenotype.

Which of the following is not a catecholamine?

Histamine

Which symptom is not characteristic of PTSD?

Hyperactivity

In the rat, estrogen receptors are densely distributed in which brain region?

Hypothalamus

Which of the following provides an example of a second messenger producing another second messenger?

IP3 binds to its receptor, enabling the release of Ca2+ from the cytosol

Which statement about LTP is false?

If one synapse (A) is very strongly stimulated (sufficient to cause LTP), and a nearby synapse (B) on the same cell is weakly stimulated a few seconds later, then the second synapse (B) will also show LTP

Which statement best describes the electrical properties of nerve cells?

In comparison to copper wires, they are relatively poor conductors of electricity

Which evidence suggests that dopaminergic input to the striatum may contribute to reward-related modulation of behavior?

In monkeys, latencies of saccades toward a target are shorter when associated with a larger reward

Which statement about the ionic permeability of cell membranes is true?

In resting nerve cells, the membrane is quite permeable to potassium.

What is the mechanism of LTP expression?

Increase in the number of postsynaptic AMPA receptors

Cholera toxin locks the Gs subunit into an active state, in that GTP is bound and cannot be hydrolyzed back to GDP to turn off the subunit. What effect will cholera toxin have in the cell?

Increased cyclic AMP levels will lead to increased protein kinase A activation

Damage to which structure would lead to dysfunction in cerebellar learning and memory functions?

Inferior olive

Selectively inhibiting gap junction channels would directly alter the activity in which region?

Inferior olive

Which experimental manipulation would prevent the formation of a partner preference in a female vole?

Injection of a D2 receptor antagonist in the nucleus accumbens

Which of the following is not an established role for glial cells?

Integrating information to assist neural computation

Damage to which pathway would affect voluntary movement of the limbs?

Interposed nuclei output to the thalamus via the superior cerebellar peduncle

Which statement regarding metabotropic and ionotropic receptors is true?

Ionotropic receptors have immediate effects; metabotropic receptors produce long-term effectsWhich statement about EPSPs in the central nervous system is true?

Which ion is transported down its concentration gradient by transporters?

Na+

Which role does calmodulin play in the intracellular cascade triggered by Ca2+?

It binds to its downstream targets when activated by Ca2+

Which statement about a nicotinic acetylcholine receptor at the neuromuscular junction is accurate?

It has two binding sites, and binding of two molecules of acetylcholine, one to each site, is required to activate the receptor

What role does Bax play in the cell during development?

It increases apoptosis

Which statement about a center-surround receptive field is false?

It is found only in primary sensory cortex

What is the role of the red nucleus?

It provides cerebellar output feedback to the inferior olive

Which statement about multiple sclerosis (MS) is false?

It was recently proven that all cases of MS are due to persistent infection by a tropical parasite

In a two-compartment model of a cell with a K+- and Ca2+-permeable membrane and a 10-fold excess of K+ in the inside compartment, how would the membrane potential change if all K+ ions were replaced by Ca2+ ions?

It would be reduced by half

How would application of an intracellular Ca2+ chelator affect the function of a synapse?

It would eliminate the postsynaptic potential and Ca2+-dependent vesicle fusion

If an aromatase inhibitor was given during perinatal development, what effect would that have on the animal?

It would prevent the masculinization by estrogen (mediated via estrogen receptors)

Which statement about kindling is true?

Its effect is long-lasting

Refer to the figure. Glutamate sensitivity (the amplitude of response to the application of glutamate) is color coded. The micrograph on the right was taken 120 minutes after the micrograph on the left. Which form of plasticity is shown in the figure?

LTP

Which stimulus is most likely to evoke an action potential?

Large depolarizing current pulse

When the right cerebellum is damaged, which cortical region loses input (either directly or indirectly)?

Left motor cortex

Which kinase is activated by the phosphorylation of its activation loop?

MAPK

Damage to which structure would prevent communication from the cingulate cortex to the anterior nucleus of the thalamus?

Mammillary body

Which structure is responsible for input only to the cerebellum?

Middle cerebellar peduncle

In what way does the function of monomeric G-proteins differ from that of heterotrimeric G-proteins?

Monomeric G-protein activation is controlled by guanine nucleotide exchange factors, heterotrimeric G-protein activation is not

What cell type does not have direct contact with Purkinje cells?

Mossy fibers

Which statement accurately describes the expression of genes in the nervous system?

Most of the genes in the human genome are expressed in the CNS

Why does the function of GABAA receptors vary among neuronal types?

Multiple types of GABAA receptor subunits exist

Which statement about myelination is false?

Myelin serves to sharply increase the time constant of the axon

Refer to the figure. What does the figure depict?

Na+/K+/Cl- co-transporter

Which regions of the cerebral cortex project directly to the striatum?

Nearly all regions of the cerebral cortex

What evidence suggests that medium spiny neurons are associated with a decision to move?

Neurons in the putamen and caudate discharge seconds before the initiation of movement

Refer to the figure. Which cell type forms the structure labeled C?

Oligodendrocytes in the central nervous system

In which way do potassium channels in the squid giant axon differ from sodium channels?

Once the potassium channels open in response to a voltage step command, they tend to remain open

Which neurotransmitters play an important role in the feeling of being in love?

Oxytocin and vasopressin

How does membrane permeability to K+ (PK) and Na+ (PNa) change during an action potential?

PK exceeds PNa at rest; PNa temporarily increases during the action potential

A hallmark of Alzheimer's disease is excessive phosphorylation of tau protein, which is thought to be due to defects in

PP2A

Which molecule is an effector directly downstream of an activated G-protein?

Phospholipase C

Which mechanism contributes to the long-term enhancement of the gill withdrawal reflex in Aplysia but is not involved in the short-term enhancement of the reflex?

Phosphorylation of CREB

Fibers from which structure(s) cross the midline prior to synapsing in the cerebellum?

Pontine nuclei

Which type of short-term synaptic plasticity lasts the longest?

Post-tetanic potentiation

Which synaptic connection would be most affected by the presence of a GABA antagonist in the cerebellum?

Purkinje cell input onto deep cerebellar nuclear cells

Which type of cell provides the only output from the cerebellar cortex?

Purkinje cells

Which nuclei comprise the striatum?

Putamen and caudate

Refer to the figure. A cat undergoes surgery to remove the brain region shown in blue in the figure. What type of behavior would you expect to see after the cat awakes from anesthesia?

Rageful

Which statement regarding Huntington's disease is false?

Recent genetic findings have led to successful gene therapy treatment and a cure

Which type(s) of electrical signals occur(s) within the neural circuit for a spinal reflex?

Receptor potential, synaptic potential, and action potential

Which treatment was shown to eliminate the early inward current in squid giant axons?

Removal of external sodium

Neurons in the CNS that release epinephrine regulate which function?

Respiration

Which state of the plasma membrane does not occur during an action potential?

Resting phase

A doctor taps the right knee in an individual who was in a car accident and has sustained damage to the right dorsal root of the lower spinal cord. Which motor response would you expect?

Right leg remains motionless

During which phase of an action potential does membrane permeability to Na+exceed membrane permeability to K+?

Rising and overshoot phases

Which cell produces myelin in the nerves of the peripheral nervous system?

Schwann cell

Refer to the figure. The figure depicts a normal action potential (left) and an action potential altered by application of a toxin (right).What are the source and mechanism of action of the toxin used?

Scorpion; slows the inactivation of Na+ channels

Which substance is a neurotransmitter that stimulates metabotropic 5-HT receptors, which have been implicated in circadian rhythm, satiety, motor behavior, and emotional state regulation?

Serotonin

A researcher is trying to study synaptic transmission in a glutamatergic hippocampal neuron. She is tasked with measuring calcium flow in the postsynaptic hippocampal neuron after either low or high intensity stimulation to the presynaptic neuron. During the experiment, she measures calcium influx after both low and high stimulation. Which statement best describes the error she made?

She forgot to add magnesium to the extracellular solution

Which statement about ionic distributions in nerve cells is true?

Sodium is higher outside cells than inside cells

Which cerebellar output is correctly paired with its function?

Spinocerebellum—motor execution

Schizophrenia and _______ are associated with mutations in MAOA and COMT genes

bipolar disorder

Excitation of the motor cortex is associated with excitation in which other brain region?

Striatum

Where are medium spiny neurons located?

Striatum

Dopaminergic neurons that synapse on medium spiny neurons originate from which brain region?

Substantia nigra pars compacta

Which region is one of the most common targets for deep brain stimulation?

Subthalamic nucleus

Which observation would demonstrate the spike timing-dependent plasticity of synapses?

Switching the relative timing of action potential and EPSP by as little as 20 ms can switch the response from LTD to LTP, or vice-versa

Which chemical signaling process is the slowest?

Synthesis of proteins after CREB activation

Which structure relays input between the cortex and the cerebellum?

Thalamus

What effect would a mutation in the estrogen receptor gene have on the development of the AVPV?

The AVPV in knockout males would be larger than control males

A rodent animal model has a mutation in the androgen receptor (AR), making it dysfunctional. If you looked at the SND-POA of adults of this mutant AR animal model, what would you expect to see?

The SDN-POA would be the same size in mutant males as in control males

Refer to the figure. What would happen if the membrane became permeable to the Y+ ions?

The Y+ ions would move into the top chamber, down their concentration gradient

Which statement correctly differentiates between the passive and active current in a myelinated axon?

The active current flows only in the nodes of Ranvier, unlike the passive current

Janet is examining slides containing male vole brain slices. She determines the vole she is looking at lived a monogamous, pair-bonded lifestyle. What did she see on the slides that led her to that conclusion?

The animal had a high density of vasopressin receptors in the ventral pallidum

Which evidence supports the assertion that the macroscopic Na+ current is the sum of many microscopic Na+ currents?

The averaged collective response of single channels resembles the time course of the macroscopic current

A female mouse is treated during development with testosterone. What effect would this have on the development of the spinal nucleus of the bulbocavernosus (SNB) system?

The bulbocavernosus muscle would be present, and the number of motor neurons present would be more than controls

A neuron has received enough stimulation to fire an action potential; it also has been treated with TEA, a K+ channel blocker. Which outcome is possible?

The cell will initially depolarize, but repolarization will take much longer because it relies only on ion pumps

Which statement on the rising or overshoot phase of the action potential is true?

The degree of depolarization is limited in part by the inactivation time course for the sodium current

Refer to the figure. Which of the following is the key event at the membrane potential of 65 mV?

The early and late currents flow outward

A dull probe stimulates a Pacinian corpuscle. An electrode is placed midway down the axon, and action potentials are recorded. After one second, the probe is pushed with greater force. What change will occur in the recording?

The frequency of action potentials will increase

A transgenic mouse animal model is created that expresses both the Cre recombinase gene, under control of a promoter for a gene expressed only in muscle fibers, and an androgen receptor with loxP sites around exon 2. How will expression of the androgen receptor protein be altered in the transgenic mouse?

The mouse will not express androgen receptor in muscle fibers

Which is not a feature of glutamate signaling systems?

The passage of large amounts of magnesium and calcium by NMDA receptors

A lab rat undergoes fear conditioning training in which a soft tone is paired with an electric shock. However, after repeated tests, the rat does not show freezing behavior in response to the tone alone. What could explain this result?

The rat had received an injection of an NMDA receptor antagonist in its amygdala

Which statement regarding refractory periods is true?

The refractory period ends when the sodium channels are no longer inactivated

Which statement about lateralization of emotional processing is true?

The right hemisphere is involved in the perception and expression of emotion

Which process(es) underlie(s) the refractory period?

The slow time course of turning off K+ conductance activation and the persistence of Na+ conductance inactivation

Refer to the figure. The function of which synapse is altered during sensitization?

The synapse between the sensory neuron of the siphon and the motor neuron

Which statement does not describe one of the findings of Bard and Hess's studies of emotion?

The visceral and somatic motor aspects of emotion are mediated by a common brain circuit

Which statement about EPSPs in the central nervous system is true?

Their effect in the central nervous system can be nullified by IPSPs

A researcher studying synaptic transmission in a glutamatergic hippocampal neuron attempts to measure calcium flow in the postsynaptic hippocampal neuron after either low or high intensity stimulation to the presynaptic neuron. Predict the results of the different stimulations.

There will be an influx calcium after high intensity stimulation

In an experiment on an animal model in which the synapsin gene is knocked out, you measure the density of synaptic vesicles in the presynaptic terminal within the active zone and outside the active zone in both knockout and control animals. Given what you know about the function of synapsin, what would you expect to find?

There will be fewer vesicles in the reserve pool in knockout animals than in controls

Which statement best describes most neurons?

They are polarized

What role do climbing fibers play in the cerebellum?

They lead to long-term potentiation, which increases the strength of parallel fiber synapses

Which statement about active ion transporters is true?

They move certain ions against the concentration gradient

Which statement about astrocytes is true?

They play a role in the formation of the blood-brain barrier

What do microscopic and macroscopic Na+ currents have in common?

They represent a flow of many ions

Which statement about silent synapses is true?

They transmit information at a resting membrane potential

Which statement about dendritic spines is false?

They usually contain just three proteins: NMDA receptors, mGluR receptors, and CaM kinase II

In a two-compartment model of a cell with a K+-permeable membrane and a 10-fold excess K+ in the inside compartment, the membrane potential is experimentally made more negative than the K+ equilibrium potential. How would K+ ions flow across the membrane?

They would flow from the outside compartment to the inside compartment

Which region sends dopaminergic inputs to the nucleus accumbens?

Ventral tegmental area

Which cerebellar structure is correctly paired with its function?

Vestibulocerebellum—posture

To date, which observation is not part of the experimental evidence favoring the vesicular release hypothesis of neurotransmission?

Visualization of acetylcholine molecules diffusing out of the neck of the membrane-fused vesicle

Which of the following does not contribute to maintaining low levels of calcium in resting nerve cells?

Voltage-gated calcium channels

The proteins that establish ionic gradients are called

active transporters

The amplitude of the action potential of a given neuron is

always the same

Ventral divisions of the basal ganglia receive excitatory inputs from the

anterior cingulate

An inability to express emotion through modulation of speech is called

aprosodia

Structures that form the voltage sensors of K+ channels

are embedded in the cell membrane

In the mature central nervous system, glial stem cells with the properties of astrocytes can give rise to

astrocytes, oligodendrocytes, and neurons

In associative learning studies in monkeys, subjects that had been successfully conditioned to a stimulus showed _______ dopaminergic neural activity in the ventral tegmental area _______.

decreased; when the predicted reward was withheld

An action potential occurs if current injected into a neuron _______ the neuron to reach _______ potential.

depolarizes; threshold

Firing an action potential in an axon initially causes a 10-mV depolarization (EPSP) in a postsynaptic neuron, but after applying a certain stimulus to the axon, firing it causes an 8-mV depolarization after each action potential. This phenomenon is called synaptic

depression

The basal ganglia are thought to elicit movement via

disinhibition of thalamic neurons (VA/VL)

Presynaptic and postsynaptic neurons that form _______ synapses are connected via _______.

electrical; gap junctions

The capability of a nerve terminal to rapidly and dramatically produce very large changes in calcium levels is most dependent on the

enormous gradient of calcium across the membrane

LTP represents a lasting increase in the size of EPSP

following a high-frequency train of stimuli

SNARE proteins participate in vesicle exocytosis by

forming a protein complex that pulls the vesicle membrane against the plasma membrane

Nodes of Ranvier represent

gaps in myelin wrapping

Efferent neurons from the globus pallidus that influence the activity of the motor areas of the cortex arise from the _______ segment and relay in the _______ before reaching the cortex.

internal; VA/VL thalamic nuclei

The effector molecule at the synapse of an intercellular signal transduction process is a(n)

ion channel

Postsynaptic currents produced by AMPA glutamate receptors are _______ than those produced by other ionotropic glutamate receptors.

larger

The voltage clamp method controls the _______ at any desired level.

membrane potential

D1 and D2 receptors are _______, with D1 receptors _______ cAMP and D2 receptors _______ cAMP.

metabotropic; increasing; decreasing

In a two-compartment model of a cell with a K+-permeable membrane, at K+ equilibrium potential, there is _______ flux of K+ ions.

no net

Refer to the figure. In the phase labeled B, the voltage-gated sodium channels are ________ and the voltage-gated potassium channels are ________.

open; closed

The _______ most directly affects the rate of information processing within the central nervous system.

propagation speed of action potentials

The part of a synapse to which the contents of synaptic vesicles bind is called the

receptor

The current flowing through individual ion channels

reflects the passage of thousands of ions per millisecond

Sexually dimorphic somatic structures and neural brain circuits are most prominently involved in

reproductive and parenting behaviors

Focal application of a GABA receptor agonist within the substantia nigra pars reticulata would most likely

result in involuntary saccadic eye movements

A surprising result that emerged from the molecular and genetic analysis of ion channels was the

sheer number of different ion channels

At -10 mV, end plate current is _______ in amplitude and directed _______.

small; inward

The technique that first revealed the tremendous diversity of neuronal cell types, by revealing different cell bodies along with their processes, is

the Golgi technique (stain)

The key aspect of receptor-gating in the associative induction of hippocampal LTP is that

the NMDA receptor acts as a molecular coincidence detector

When current is injected into an axon,

the current will decay exponentially with increasing distance from the injection site (if no action potential is present)

The squid giant axon is useful in neuronal studies because

the cytoplasm in the axon can be extruded, thus allowing studies of its composition

The most mysterious aspect of emotional experience is

the highly subjective "feelings" that attend many emotional states

Unconventional neurotransmitters

transmit signals between neurons

A K+ inward rectifier channel has

two transmembrane domains and a pore loop, but no voltage sensor

The in situ hybridization method is based on

using nucleic acid probes to detect mRNAs that encode specific genes

The most important factor determining whether a receptor-operated ion channel is inhibitory or excitatory is

whether the permeant ion's reversal potential is positive or negative to threshold

Which neurons do not directly synapse on the striatum?

α motor neurons