NERVOUS SYSTEM PRACTICE QUESTIONS

•Which spinal tract carries action potentials generated by pain receptors? • -a. Fasciculus cuneatus of the posterior column pathway -b. Latera Fasciculus gracilis tract -c. Lateral spinothalamic tract -d. Anterior spinothalamic tract

-c. Lateral spinothalamic tract

A person with polio has lost the use of his leg muscles. In which area of his spinal cord would you expect the virus-infected motor neurons to be? a. Anterior gray horns b. Lateral gray horns c. Posterior gray commissure d. Anterior gray white commissure

a. Anterior gray horns

Why are spinal nerves classified as "mixed" nerves? a. Because they contain both afferent and efferent fibers. b. Because they contain the cell bodies of sensory neurons that travel the dorsal and ventral ramus. c. Because they carry mixed or conflicting information. d. Because axons of the ventral root carry sensory information to the spinal cord and axons of the dorsal root control somatic and visceral effectors.

a. Because they contain both afferent and efferent fibers.

Why can damage to the medulla oblongata cause death? a. It contains cardiac, vasomotor, and respiratory centers. b. It controls the ANS. c. It contains tracts that process information to and from the cerebellum. d. It contains the headquarters for the reticular activating system.

a. It contains cardiac, vasomotor, and respiratory centers.

The ___ carries sensation of highly localized (fine) touch, while the ___ provides conscious sensations of poorly localized (crude) touch? a. Posterior column pathway / anterior spinothalamic tract b. Fasciculus gracilis / fasciculus cuneatus c. Spinocerebellar pathway / lateral spinothalamic tracts d. Spinothalamic pathway / spinocerebellar pathway

a. Posterior column pathway / anterior spinothalamic tract

Receptor A has a circular receptive field with a diameter of 2.5 cm. Receptor B has a circular receptive field of 7.0 cm in diameter. Which receptor allows you to more precisely localize a stimulus? a. Receptor A b. They would provide the same precision of sensory information. c. Receptor B d. It would depend on the location of the receptors.

a. Receptor A

When a person always leans their head on their hand in order to stay awake in class this can put pressure on the elbow and damage the _______. a. Ulnar nerve b. Median nerve c. Radial nerve d. Musculocutaneous nerve

a. Ulnar nerve

How would decreased diffusion cross the arachnoid granulations affect the volume of cerebrospinal fluid in the ventricles? a. Volume would increase. b. Volume would decrease. c. Volume would remain the same. d. Volume would fluctuate erratically.

a. Volume would increase.

The medial pathway controls ____, whereas the lateral pathway controls _____. a. gross movements of the trunk and proximal limb muscles; distal limb muscles and precise movement b. background patterns of movement; motor impulses from the cerebrum to the spinal cord c. subconscious control of balance and muscle tone; subconscious control of reflex activity d. none of the above

a. gross movements of the trunk and proximal limb muscles; distal limb muscles and precise movement

The _____ carries sensation of highly localized (fine) touch, while the _____ provides conscious sensations of poorly localized (crude) touch. a. posterior column pathway; anterior spinothalamic tract b. fasciculus gracilis; fasciculus cuneatus c. spinocerebellar pathway; lateral spinothalamic tract d. spinothalamic pathway; spinocerebellar pathway

a. posterior column pathway; anterior spinothalamic tract

Which of the following motor pathways remains uncrossed along its length? a. vestibulospinal tract b. tectospinal tract c. anterior corticospinal tract d. lateral corticospinal tract

a. vestibulospinal tract

What effect would blocking voltage-gated calcium channels at a cholinergic synapse have on synaptic communication? a.Communication would cease. b.Communication would be enhanced. c.Communication would be misdirected. d.Communication would continue as before.

a.Communication would cease.

Which of the following is TRUE concerning neuromodulators? a.have long-term effects b.act immediately without intermediate steps c.affect neither postsynaptic nor presynaptic membrane d.none of the above

a.have long-term effects

Which of these is NOT usually a characteristic function associated with the left cerebral hemispheres? a. Performing mathematical calculations b. Analyzing emotional context of a conversation c. Containing the general interpretive and speech centers d. Processing associated with reading, writing, and speaking

b. Analyzing emotional context of a conversation

What is unusual about the posterior spinocerebellar tracts when compared with other ascending pathways? a. The decussation of axons in the medulla innervate motor neurons on the opposite side of the body. b. Axons enter the posterior spinothalamic tract on the same side of the body .c. They are the only tracts to carry information about referred pain. d. They carry information along visceral sensory pathways.

b. Axons enter the posterior spinothalamic tract on the same side of the body

Many water-soluble molecules that are relatively abundant in the blood occur in small amounts or not at all in the extracellular fluid in the brain. Why? a. Blood pressure increases in brain capillaries. b. Blood-brain barrier restricts ion movement. c. Neurons take up most ions. d. Neuroglia remove ions from CSF.

b. Blood-brain barrier restricts ion movement.

Injury to which nerve plexus would interfere with the ability to breathe __? Which nerve is the major nerve of this plexus? a. Brachial plexus / long thoracic nerve b. Cervical plexus / phrenic nerve c. Cervical plexus / long thoracic nerve d. Brachial plexus / pectoral nerve

b. Cervical plexus / phrenic nerve

Which portion of the spinal cord would be affected by a disease that damages myelin sheaths? a. Sulci b. Columns c. Gray horns d. Fissures

b. Columns

What name is given to axons/tracts carrying information between the cerebral hemispheres of the brain? a. Projection fibers b. Commissural fibers c. Association fibers d. Arcuate fibers

b. Commissural fibers

Why is cerebellar control over well-practiced movements, such as swinging a baseball bat, important? a. Voluntary movements begin with activation of far fewer motor units than necessary. b. Concentrating on voluntary control using the motor cortex disrupts the pattern and rhythm. c. Patterns of movement are unchanging. d. Both A and B are correct.

b. Concentrating on voluntary control using the motor cortex disrupts the pattern and rhythm.

Parkinson's disease manifests which of the following abnormalities? a. The motor cortex ceases receiving messages from sensory neurons. b. Excitatory neurons in the basal nuclei become more active, leading to faulty control of voluntary movements. c. Axons that synapse in the thalamus no longer convey messages to the motor cortex. d. GABA is released by neurons in excessive amounts.

b. Excitatory neurons in the basal nuclei become more active, leading to faulty control of voluntary movements.

As a result of pressure on her spinal cord, Jill cannot feel touch or pressure on her lower limbs. Which spinal tract is being compressed? a. Fasciculus cuneatus b. Fasciculus gracilis c. Lateral spinothalamic tract d. Anterior spinothalamic tract

b. Fasciculus gracilis

Polysynaptic reflexes include all of he following characteristics, except ___? a. Involve pools of interneurons b. Interneuron pools are contained within one spinal segment c. Have reverberating circuits d. Involve reciprocal inhibition

b. Interneuron pools are contained within one spinal segment

Which of the cerebellar peduncles allows communication between the cerebellum and pons? a. Transverse cerebellar peduncles b. Middle cerebellar peduncles c. Inferior cerebellar peduncles d. Superior cerebellar peduncles

b. Middle cerebellar peduncles

Reflex responses usually remove or oppose the stimulus. Therefore this type of reflexive response would be considered an example of ___. a. A visceral reflex b. Negative feedback c. A reverberation circuit d. Avoidance feedback

b. Negative feedback

Conscious perception of which senses would be affected by damage to the temporal lobes of the cerebrum? a. Olfactory and gustatory b. Olfactory and auditory c. Visual and auditory d. Auditory and gustatory

b. Olfactory and auditory

A patient has damage to several spinal nerves. Which of the major divisions of the nervous system has been damaged? a. Central nervous system b. Peripheral nervous system c. Autonomic nervous system d. All of these are correct.

b. Peripheral nervous system

Reflex movements of the upper limbs are controlled by what nuclei of the mesencephalon? a. Substantia nigra b. Red nucleus c. Inferior colliculi d. Superior colliculi

b. Red nucleus

Which primary brain vesicle is destined to form the hindbrain structures? a. Prosencephalon b. Rhombencephalon c. Myelencephalon d. Metencephalon

b. Rhombencephalon

Compression of which nerve bothers older people on long car rides? a. Sural nerve b. Sciatic nerve c. Femoral nerve d. Tibial nerve

b. Sciatic nerve

Damage to the lateral geniculate nuclei of the thalamus would interfere with the functions of which of the senses? a. Taste b. Sight c. Touch d. Smell

b. Sight

What is the minimum number of neurons in a reflex arc? a. One b. Two c. Five d. Seven

b. Two

In the stretch reflex the receptor stimulated is called a _______. The effector is the _______ muscle. a. golgi tendon, same b. muscle spindle, same c. golgi tendon, opposite d. muscle spindle, opposite

b. muscle spindle, same

Nociceptors are _______. They are sensitive to ______. a. thermoreceptors; extremes of temperature and changes in vibration b. pain receptors; extremes of temperature, mechanical damage, and chemicals released from injured cells c. pain receptors; changes in pressure or stretch in muscles d. chemoreceptors; changes in concentration of chemicals or compounds

b. pain receptors; extremes of temperature, mechanical damage, and chemicals released from injured cells

Somatic sensory pathways carry information from the _____ and the _______ of the head, neck, limbs, and body wall. a. liver; epithelia b. skin; muscles c. sweat glands; connective tissue d. none of the above

b. skin; muscles

The relationship between a neurotransmitter, such as NE and a cytosolic compound, such as cAMP, is that they are _____, which is enhanced by a "link" called a _____. a.both amino acids; carboxyl group b.1st messenger and 2nd messenger; G protein c.neurotransmitters; 2nd messenger d.EPSP and IPSP; 1st messenger

b.1st messenger and 2nd messenger; G protein

In what ways are temporal and spatial summation the same? a.Both require a rapid succession of stimuli at a single synapse. b.Both are methods by which individual EPSPs combine to result in an action potential. c.Both occur when simultaneous stimuli are applied at different locations, causing a cumulative effect on transmembrane potential. d.All of the above are correct.

b.Both are methods by which individual EPSPs combine to result in an action potential.

Which structure of a neuron is capable of propagating an electrical impulse? a.dendrite b.axon c.cell body d.perikaryon

b.axon

Since neurons lack _____, they cannot undergo _____. a.Nissl bodies; endocytosis b.centrioles; cell division c.nuclei; meiosis d.chromosomes; cell respiration

b.centrioles; cell division

What is the primary distinction between chemical and electrical synapses? Which type is more rare? a.electrical synapses involve a neurotransmitter; chemical synapses b.electrical synapses involve direct connection between cells; electrical synapses c.chemical synapses involve direct connection between cells; chemical synapses d.electrical synapses always use ACh; both are equally abundant

b.electrical synapses involve direct connection between cells; electrical synapses

The gated channels that respond to physical distortion of the membrane surface are called _____. These channels are important in _____. a.chemically gated channels; dendrites b.mechanically gated channels; sensoryreceptors c.voltage-gated channels; axons of multipolar and unipolar neurons d.passive channels; areas where the channels must remain open

b.mechanically gated channels; sensoryreceptors

Which of the CNS neuroglial cells function as phagocytic cells? a.satellite cells b.microglia c.oligodendrocytes d.astrocytes

b.microglia

Bundles of axons in the peripheral nervous system are also known as _____. a.tracts b.nerve fibers c.vessels d.none of the above

b.nerve fibers

What is reinforcement as it pertains to spinal reflexes? a. It allows brief periods of rest between sets of stimuli b. A chronic depression in spinal reflexes due to IPSPs c. An enhancement of spinal reflexes due to postsynaptic neurons entering a state of facilitation d. Strengthening of both the crossed extensor reflex and reciprocal inhibition

c. An enhancement of spinal reflexes due to postsynaptic neurons entering a state of facilitation

An anesthetic blocks the function of the dorsal rami of the cervical spinal nerves. Which areas of the body will be affected? a. Skin and muscles of the back of the neck b. Skin and muscles of the shoulders c. Both A and B d. None of the above

c. Both A and B

During a withdrawal reflex, what happens to the limb on the side opposite the stimulus? What is the response called? a. Flexed / stretch reflex b. Adducted / tendon reflex c. Extended / crossed extensor reflex d. Abducted / tendon reflex

c. Extended / crossed extensor reflex

What statement below is NOT true with regard to the cranial dura mater and the spinal dura mater? a. In the brain it is formed of two layers. b. In the brain some portions extend into the cranial cavity as the dural folds. c. In the spinal column it contains the dural sinuses. d. In the brain there is not epidural space..

c. In the spinal column it contains the dural sinuses.

One of the first somatic reflexes to develop is the suckling reflex. Which type of reflex is this? a. Inherent reflex b. Acquired reflex c. Innate reflex d. Visceral reflex

c. Innate reflex

Someone with paralysis of the anterior thigh muscle would have damage at which spinal segments? a. L4 - S4 b. T12 - L1 c. L2 - L4 d. L4 - S2

c. L2 - L4

Which area of the diencephalon would be stimulated by changes in body temperature? a. Tuberal area of the hypothalamus b. Anterior nuclei of the thalamus c. Paraventricular area of the hypothalamus d. Intermediate mass of the thalamus

c. Paraventricular area of the hypothalamus

A patient suffers a head injury that damages her primary motor cortex. Where is the primary motor cortex and what functions will be lost due to the injury? a. Parieto-occipital sulcus / control over involuntary movements b. Postcentral gyrus / voluntary movements controlled by the specific regions damaged c. Precentral gyrus / voluntary movements controlled by the specific regions damaged d. Insula / ability to categorize items

c. Precentral gyrus / voluntary movements controlled by the specific regions damaged

Damage to the amygdaloid body would interfere with regulation of what division of the autonomic nervous system? a. Peripheral b. Somatic c. Sympathetic d. Parasympathetic

c. Sympathetic

What brain regions make up the brain stem? a. The hypothalamus, the thalamus, and the pons b. The diencephalon and the mesencephalon c. The mesencephalon, the pons, and the medulla oblongata d. The pons, the cerebellum, and the medulla oblongata

c. The mesencephalon, the pons, and the medulla oblongata

Which nuclei in the medulla oblongata are responsible for relaying somatic sensory information to the thalamus? a. Nuclei of superior and inferior colliculi b. Nuclei of cranial nerves VIII - XII c. The nucleus gracilis and the nucleus cuneatus d. The solitary nucleus and olivary nucleus

c. The nucleus gracilis and the nucleus cuneatus

Which of following is true concerning the spinal cord ? a. The filum terminale is the end of the spinal cord and stabilizes the cord. b. The conus medullaris is a strand of fibrous tissue that helps support the spinal cord. c. The spinal cord of an adult ends between L1 and L2. d. The amount of gray matter in the spinal cord is the least at the cervical and lumber enlargements.

c. The spinal cord of an adult ends between L1 and L2.

A patient who is hooked up to an EEG shows primarily beta waves. What are they doing? a. They are in deep sleep or have a brain disorder. b. They are in the early stages of sleep. c. They are concentrating on a specific task. d. They are extremely frustrated.

c. They are concentrating on a specific task.

Distinguishing facts concerning tonic receptors include all of the following EXCEPT: a. Tonic receptors are always active. b. The frequency of action potential generation indicates the background level of stimulation. c. Tonic receptors are active for a short time whenever a change occurs in conditions monitored. d. When a stimulus increases or decreases the rate of action potential generation changes.

c. Tonic receptors are active for a short time whenever a change occurs in conditions monitored.

The substantia nigra is a nuclei is that secretes the neurotransmitter _______. a. acetylcholine b. norepinephrine c. dopamine d. GABA

c. dopamine

Which spinal tract carries action potentials generated by nociceptors? a. fasciculus cuneatus b. fasciculus gracilis c. lateral spinothalamic tract d. anterior spinothalamic tract

c. lateral spinothalamic tract

All _____ pathways send information to the _______ when motor commands are issued .a. sensory; thalamus b. motor; pons c. motor; cerebellum d. sensory; cerebellum

c. motor; cerebellum

Axon A propagates signal at 50 m/sec and axon B propagates signal at 1 m/sec. What is the structural difference between these axons? a.Axon A has a smaller diameter than axon B. b.Axon B is myelinated. c.Axon A is myelinated. d.None of the above is correct.

c.Axon A is myelinated.

Which of the choices below correctly lists the steps of an action potential? a.resting potential ➔ absolute refractory period ➔ relative refractory period b.all-or-none principle ➔ stimulus triggers action potential ➔ stimulus does not trigger action potential c.depolarization to threshold ➔ activation of sodium channels and depolarization ➔ inactivation of sodium channels and activation of potassium channels ➔return to normal permeability d.none of the above

c.depolarization to threshold ➔ activation of sodium channels and depolarization ➔ inactivation of sodium channels and activation of potassium channels ➔return to normal permeability

Which type of neuroglia would be found lining the hollow regions of the CNS? a.astrocytes b.microglia c.ependymal cells d.oligodendrocytes

c.ependymal cells

The functional classification of neurons that are responsible for integrating sensory information with motor output are called _____. These neurons are located _____. a.motor neurons; in the anterior horn of the spinal cord b.proprioceptors; in skeletal muscles and joints c.interneurons; almost exclusively in the CNS d.interoceptors; in the digestive,respiratory, and cardiovascular systems

c.interneurons; almost exclusively in the CNS

The synapse between a neuron and a muscle cell is called a _____. a.gap junction b.desmosome c.neuromuscular junction d.intercalated disc

c.neuromuscular junction

Neuroglia of the PNS include _____ and _____, and their respective functions are _____ and _____. a.astrocytes; oligodendrocytes; guide axon regeneration; myelinate axons b.ependymal cells; Schwann cells; form cerebrospinal fluid; form myelin sheath c.satellite cells; Schwann cells; regulate O2, CO2, nutrient, and transmitter levels; myelinate axons d.microglia; ependymal cells; regulate environmentaround neurons; form cerebrospinal fluid

c.satellite cells; Schwann cells; regulate O2, CO2, nutrient, and transmitter levels; myelinate axons

The two functional divisions of the peripheral nervous system are the afferentand efferent divisions. What are their respective functions? a.control of the central nervous system; control of the peripheral nervous system b.control of neurons; control of neuroglia c.sensory input to the CNS; carries motorcommands to muscles or glands d.carries motor commands to muscles or glands; sensory input to the CNS

c.sensory input to the CNS; carries motorcommands to muscles or glands

What are potential consequences of blockage of an interventricular foramen? a. Hugely expanded skulls in infants b. Brainstem stroke c. Damage to and distortion of brain in adults d. A and C are correct

d. A and C are correct

What would happen if the information from proprioceptors in your legs were blocked from reaching the CNS? a. You would not experience pain sensations from your legs b. Your lower limb movements would be uncoordinated c. You wouldn't know position or degree of stretch in tendons of your legs d. B and C are correct

d. B and C are correct

What is the clinical significance of dermatomes? a. Damage to descending tracts will be reflected in the dermatomes. b. Location of affected dermatomes provides clues to location of injury along the spinal cord. c. Damage to a corresponding spinal nerve will produce loss of sensation to the region of skin supplied by a dermatome. d. B and C are correct.

d. B and C are correct.

Where is the cerebrospinal fluid of the spinal cord located? a. Central canal b. Subarachnoid space c. Above the dura mater d. Both a and b.

d. Both a and b.

After suffering a stroke, a patient is unable to speak, but can understand what is said to him and can understand written messages. Which part of his brain has been affected by the stroke? a. Wernike's area in the parietal lobe b. General interpretive area of the temporal lobe c. Primary visual cortex in the occipital lobe d. Broca's area in the frontal lobe

d. Broca's area in the frontal lobe

What is the primary function of the cerebellum? a. Controls reflexive movements of the eyes in response to visual stimuli b. Provides awareness of emotional states c. Coordination between voluntary and autonomic functions d. Coordinates rapid, automatic adjustments that maintain balance and equilibrium

d. Coordinates rapid, automatic adjustments that maintain balance and equilibrium

For what anatomical reason does the left side of the brain control motor function on the right side of the body? a. Motor function is controlled by a system two neurons b. Motor function is controlled by cranial reflexes c. The motor area devoted to a particular areabecomes larger d. Decussation of axons

d. Decussation of axons

What symptoms would you expect to observe in an individual who has damage to the basal nuclei? a. Mental slowness and inability to perceive meaning form written symbols b. Conscious perception of touch and erratic muscle contractions c. Epileptic seizures d. Difficulty starting voluntary movements and decreased muscle tone

d. Difficulty starting voluntary movements and decreased muscle tone

Which of the following is NOT a function of the limbic system? a. Establishing emotional states b. Linking the conscious, intellectual function of the cerebral cortex with unconscious autonomic functions of the brain stem c. Facilitating memory storage and retrieval d. Directing somatic motor patterns associated with rage, pleasure, and pain

d. Directing somatic motor patterns associated with rage, pleasure, and pain

Into which structure would a saddle-block anesthesia be administered? a. Dura mater b. Arachnoid mater c. Subarachnoid space d. Epidural space

d. Epidural space

Which structure is associated with the diencephalon is responsible for the secretion of melatonin that regulates day and night cycles? a. Thalamus b. Pituitary gland c. Hypothalamus d. Epithalamus

d. Epithalamus

Which cranial nerve nuclei are located inthe medulla oblongata? a. VII, IX, and X b. III, IV, and VI c. V, VI, VII, and VIII d. IX, X, XI, and XII

d. IX, X, XI, and XII

Which of the following is incorrect concerning chemoreceptors? a. They are located in the fourth ventricle of the brain and so we are not consciously aware of the sensations they provide. b. Chemoreceptive neurons are located in the carotid bodies and aortic bodies. c. Chemoreceptors monitor the levels of respiratory gases in blood and CSF. d. None of the above statements are incorrect.

d. None of the above statements are incorrect.

After injuring her back, Tina, 18 years old, exhibits a positive Babinski reflex. What does this imply about Tina's injury? a. Possible paraplegia b. Possible damage of sensory tracts to foot c. Possible damage of ascending tracts in spinal cord d. Possible damage of descending tracts in the spinal cord

d. Possible damage of descending tracts in the spinal cord

Which is the term used when a postsynaptic neurons axon collateral stimulates the presynaptic neuron? a. Parallel processing b. Convergence c. Divergence d. Serial processing

d. Serial processing

Damage to the long thoracic nerve would cause paralysis to which muscle(s)? a. Deltoid and teres minor muscles b. Rhomboids and levator scapulae muscles c. Latissimus dorsi muscle d. Serratus anterior muscle

d. Serratus anterior muscle

You've just touched a hot stove. What type of reflex did you experience __ and in what way was your brain involved in the reflex __? a. Cranial / the somatosensory cortex b. Visceral / only tracts that respond to pain c. Complex / all the sensory tracts d. Spinal / it was advised later

d. Spinal / it was advised later

A weight lifter is straining to lift a 200-kg barbell. Shortly after he lifts it to chest height, his muscles appear to relax and he drops the barbell. Which reflex has occurred? a. Withdrawal reflex b. Stretch reflex c. Crossed extensor reflex d. Tendon reflex

d. Tendon reflex

Which of these is NOT an important factor concerning reflexes? a. They are rapid, automatic responses to stimuli. b. They preserve homeostasis by making rapid adjustments in the functions of organs. c. They oppose potentially harmful changes in the internal or external environment. d. They involve interaction with the cerebrum.

d. They involve interaction with the cerebrum.

If a sensation is to reach your conscious awareness, there must be a synapse with a ___ in the ___? a. First-order neuron / thalamus b. Second-order neuron / primary sensory cortex c. First-order neuron / dorsal root ganglion d. Third-order neuron / thalamus

d. Third-order neuron / thalamus

The cerebellum monitors proprioceptive information for which two senses? a. Visual and hearing b. Hearing and postural information c. Taste and smell d. Vestibular and visual

d. Vestibular and visual

The superior colliculus is a ______ reflex center while the inferior colliculus is a ______ reflex center. a. visual, tactile b. auditory, visual c. olfactory, visual d. visual, auditory

d. visual, auditory

Which of the following statements is (are) TRUE with regard to saltatory propagation? a.Myelinated areas of the axon accelerate propagation. b.Only nodes along a myelinated axon can respond to a depolarizing stimulus. c.Continuous propagation uses less energy, and fewer sodium ions must be pumped out. d.Both A and B are correct.

d.Both A and B are correct.

Enhancing the effects of the neurotransmitter _____ has allowed pharmaceutical companies to produce medications that decrease anxiety. a.serotonin b.norepinephrine c.acetylcholine d.GABA

d.GABA

Effectors include which of the following? a.glands b.muscles c.adipose tissue d.all of the above

d.all of the above

Excitatory neurotransmitters cause _____, and inhibitory neurotransmitters _____. a.repolarization; return to resting potential b.suppression of generation of action potentials; promote generation of action potentials c.synaptic fatigue; cause synaptic delay d.depolarization; cause hyperpolarization

d.depolarization; cause hyperpolarization

What effect would decreasing the concentration of extracellular potassium ions have on the transmembrane potential of a neuron? a.repolarization b.hypopolarization c.decreased transmembrane potential d.hyperpolarization

d.hyperpolarization

Which of these is NOT a site at which acetylcholine is released at a synapse? a.at neuromuscular junctions with skeletal muscles b.at ganglionic neuron-to-neuron synapses in the ANS c.sometimes at postganglionic synapses in the sympathetic division of the ANS d.none of the above

d.none of the above

A person you know has experienced sleep problems and prolonged depression. Which neurotransmitter may be in short supply? a.dopamine b.any of the opioids c.acetylcholine d.serotonin

d.serotonin

The effects of a neurotransmitter on the postsynaptic membrane depend on the _____. a.time involved in calcium influx across the synapse b.rate of enzyme inhibition c.properties of the release of neurotransmitter d.type of receptor

d.type of receptor

Which type of voltage-gated channels are located just beyond the axon hillock? a.voltage-gated potassium channels b.voltage-gated calcium channels c.voltage-gated chloride channels d.voltage-gated sodium channels

d.voltage-gated sodium channels