Anatomy and Physiology Chapter 12

Somatic motor neuron axons fall into the category of A. A fibers. B. B fibers. C. C fibers. D. D fibers.

A. A fibers.

Which occurs first? A. Absolute refractory period B. Relative refractory period

A. Absolute refractory period

What is the most abundant glial cell in the CNS? A. Astrocyte B. Ependymal cell C. Neurolemmocyte D. Microglial cell E. Oligodendrocyte

A. Astrocyte

Where are synaptic knobs located? At the tips of telodendria At the ends of dendrites Within the cell body Along axon collaterals At the axon hillock

A. At the tips of telodendria

You walk into a restaurant and amidst the sights, sounds, and smells of food preparation, you notice that you have begun to salivate. This is evidence that a particular neuronal circuit has been activated. Which one? A. Converging B. Diverging C. Reverberating D. Parallel-after-discharge E. None of the choices is correct.

A. Converging

When a neurotransmitter opens a chemically gated ion channel that allows sodium to enter the postsynaptic cell, the result is an A. EPSP. B. IPSP.

A. EPSP.

Which statement is true regarding the action of an oligodendrocyte? A. Each oligodendrocyte can form a myelin sheath around many axons simultaneously. B. An oligodendrocyte is responsible for forming part of the blood-brain barrier. C. Oligodendrocytes function only within the PNS. D. Each oligodendrocyte can wrap only a 1-mm portion of a single axon. E. A neurolemmocyte attacks pathogens.

A. Each oligodendrocyte can form a myelin sheath around many axons simultaneously.

Which is not characteristic of neurons? High mitotic rate High metabolic rate Require continuous supplies of glucose and oxygen Extreme longevity No exceptions; all of these are characteristic of neurons.

A. High mitotic rate

Which of the following is false regarding acetylcholine? A. It is rarely used in the body. B. It is the neurotransmitter used at the neuromuscular junction. C. It is stored and released by the presynaptic cell. D. It is synthesized from acetic acid and choline.

A. It is rarely used in the body.

A scientist observes a particular nerve fiber that is among the fastest at conducting action potentials in the body. Which of the following best describes its likely structure? A. Large diameter and myelinated B. Large diameter and unmyelinated C. Small diameter and myelinated D. Small diameter and unmyelinated

A. Large diameter and myelinated

Which statement accurately compares the transmission speed of the different types of synapses? A. Transmission at chemical synapses involves a brief synaptic delay, but electrical synapses are faster. B. Transmission at both chemical and electrical synapses involves a synaptic delay of approximately 1 millisecond. C. Transmission at electrical synapses involves a brief synaptic delay, but chemical synapses are faster. D. Electrical synapses have a constant delay of 1 millisecond, but chemical synaptic delays vary between 0.1 and 0.3 millisecond.

A. Transmission at chemical synapses involves a brief synaptic delay, but electrical synapses are faster.

Which is not a general function of the nervous system? A. Transporting materials throughout the body B. Collecting information C. Processing and evaluating information D. Responding to information E. No exceptions; all are general functions of the nervous system.

A. Transporting materials throughout the body

A graph of an EPSP would plot time against a voltage trace that would resemble A. a hill where the high point approaches the threshold value. B. a hill where the high point is the farthest away from the threshold value. C. a valley where the low point approaches the threshold value. D. a valley where the low point is the farthest away from the threshold value.

A. a hill where the high point approaches the threshold value.

Conductive activity in a neuron generally causes it to secrete a specific neurotransmitter that either excites or inhibits its target. a specific neurotransmitter that always excites its target. several types of neurotransmitters simultaneously, all of which excite the cell's target. several types of neurotransmitters simultaneously, that are broadcast to excite and inhibit multiple targets. several types of neurotransmitters simultaneously, that all work to prevent another immediate impulse.

A. a specific neurotransmitter that either excites or inhibits its target.

The glial cell that helps to form the blood-brain barrier is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

A. astrocyte.

The glial cell that provides structural support and organization to the CNS is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

A. astrocyte.

The glial cell with perivascular feet that wrap around capillaries in the CNS is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

A. astrocyte.

The glial cell with the responsibility of occupying the space left by dead or dying neurons is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

A. astrocyte.

A neuron conducting an impulse from the CNS to the detrusor muscle of the urinary bladder would be classified as a(n) __________ neuron. autonomic motor somatic sensory somatic motor visceral sensory

A. autonomic motor

The conductive segment of a neuron is its _______, a region that contains many _______ gated channels. A. axon, voltage- B. axon, chemically C. dendrite, voltage- D. dendrite, chemically

A. axon, voltage-

The type of transport protein that moves a substance down its concentration gradient is a A. channel. B. pump.

A. channel.

The type of neuronal circuit in which several nerve impulses come together at a single postsynaptic neuron is a _____________ circuit. A. converging B. diverging C. reverberating D. parallel-after-discharge E. None of the choices is correct.

A. converging

The main way acetylcholine is cleared from a synapse is by A. degradation by an enzyme. B. uptake by the postsynaptic cell. C. reuptake by the presynaptic cell. D. being engulfed by a supporting glial cell.

A. degradation by an enzyme.

Hyperpolarization of a neuron results from A. either the entry of an anion or the exit of a cation. B. the entry of any ion. C. either the entry of a cation or the exit of an anion. D. the entrance of either sodium or potassium.

A. either the entry of an anion or the exit of a cation.

When a neuromodulator slows the reuptake of a neurotransmitter or causes expression of an increased number of receptors on postsynaptic neurons, the effect is called A. facilitation. B. temporal summation. C. spatial summation. D. presynaptic potentiation. E. recruitment.

A. facilitation.

Vesicles and glycoproteins required at the synapse are moved down a nerve fiber by _______ axonal transport. A. fast B. slow

A. fast

If there were no sodium leak channels, the resting membrane potential of a neuron would be A. more negative. B. more positive. C. the same. D. 0 mV.

A. more negative.

Based on structure, the most common type of neuron is the _______ neuron. A. multipolar B. bipolar C. unipolar D. pseudounipolar

A. multipolar

Saltatory conduction occurs in A. myelinated axons, where action potentials occur only at neurofibril nodes. B. myelinated axons, where action potentials occur only under the myelin sheath. C. myelinated axons, where action potentials occur continuously down the entire axon. D. unmyelinated axons, where action potentials occur continuously down the entire axon. E. the axon terminal, where full-size action potentials occur at the hillock.

A. myelinated axons, where action potentials occur only at neurofibril nodes.

Arrival of an action potential at the synaptic knob results in A. opening of voltage-gated calcium channels and diffusion of calcium into the synaptic knob. B. opening of voltage-gated calcium channels and diffusion of calcium out of the synaptic knob to the interstitial fluid. C. closure of voltage-gated calcium channels in the synaptic knob membrane. D. opening of chemically gated calcium channels and diffusion of calcium into the synaptic knob. E. opening of chemically gated calcium channels and diffusion of calcium out of the synaptic knob to the interstitial fluid.

A. opening of voltage-gated calcium channels and diffusion of calcium into the synaptic knob.

When voltage-gated K+ channels open on the conductive segment of a neuron, A. potassium exits, repolarizing the cell to a negative value. B. potassium exits, depolarizing the cell to an even more negative value. C. potassium enters, depolarizing the cell to a positive value. D. potassium enters, repolarizing the cell to a negative value. E. potassium enters, repolarizing the cell to a positive value.

A. potassium exits, repolarizing the cell to a negative value.

The most crucial factor determining the resting potential of a neuron is the diffusion of A. potassium out of the cell through leak channels. B. potassium into the cell through gated channels. C. sodium out of the cell through leak channels. D. sodium into the cell through gated channels.

A. potassium out of the cell through leak channels.

The glial cell that protects neuron cell bodies located within ganglia is the A. satellite cell. B. ependymal cell. C. neurolemmocyte. D. astrocyte. E. oligodendrocyte.

A. satellite cell.

In a mixed nerve A. some axons transmit sensory information and others transmit motor information. B. individual axons transmit both sensory and motor information. C. chemical synapses occur along with electrical synapses. D. astrocytes are interspersed with ependymal cells.

A. some axons transmit sensory information and others transmit motor information.

The glossy-white appearance of most axons is due to A. the high lipid content of the myelin sheath. B. their proximity to light-reflecting cartilage. C. their proximity to white bone. D. the white color of the perivascular feet. E. the covering of ependymal cells.

A. the high lipid content of the myelin sheath.

When transmission occurs at a synapse, neurotransmitter is released by A. the presynaptic neuron's synaptic knob into the synaptic cleft. B. the postsynaptic neuron's dendrites into the synaptic cleft. C. the presynaptic neuron's dendrites into the synaptic cleft. D. the presynaptic neuron's soma into synaptic vesicles. E. the postsynaptic neuron's telodendria into the axon hillock.x

A. the presynaptic neuron's synaptic knob into the synaptic cleft.

Wallerian degeneration involves the breakdown of A. the segments of axon and myelin sheath between the site of damage and the peripheral effector. B. the segments of axon and myelin sheath between the site of damage and the cell body. C. the neurilemma both central and peripheral to the site of trauma. D. macrophages and microglia that have completed the job of CNS cleanup after trauma.

A. the segments of axon and myelin sheath between the site of damage and the peripheral effector.

Action potentials are generated by the opening of ________ gated channels and they occur on the ________. A. voltage-, axon B. voltage-, dendrite C. chemically, axon D. chemically, dendrite

A. voltage-, axon

The slowest category of nerve fibers are the A. A fibers, and they conduct impulses at 10 meters per second. B. C fibers, and they conduct impulses at 1 meter per second. C. D fibers, and they conduct impulses at 0.1 meter per second. D. C fibers, and they conduct impulses at 100 meters per second. E. D fibers, and they conduct impulses at 0.01 meter per second.

B. C fibers, and they conduct impulses at 1 meter per second.

What type of circuit is used to maintain body posture while walking? A. Converging B. Diverging C. Reverberating D. Parallel-after-discharge E. None of the choices is correct.

B. Diverging

Which statement is consistent with the current understanding of neural tissue? A person is born with all of the neurons they will ever have. Most neurons formed in fetal development last a lifetime, but some brain regions in adults can generate new neurons. Neurons are constantly dying and being replaced throughout all regions of the brain. Stem cells in the brain become glia, which can later become neurons if there is a need for them to do so.

B. Most neurons formed in fetal development last a lifetime, but some brain regions in adults can generate new neurons.

Which division of the nervous system shows a greater capacity for regeneration? A. CNS B. PNS

B. PNS

Which is not a type of neuronal pool? A. Converging B. Triangular-pre-discharge C. Diverging D. Parallel-after-discharge E. Reverberating

B. Triangular-pre-discharge

Glial cells differ from neurons in that they A. are larger and capable of meiosis. B. are smaller and capable of mitosis. C. are found only in the CNS. D. are found only in the PNS. E. transmit nerve impulses much more slowly.

B. are smaller and capable of mitosis.

In order to trigger the release of neurotransmitter from a neuron terminal, calcium ions A. exit the synaptic knob through diffusion. B. bind to proteins on the surface of synaptic vesicles. C. penetrate the synaptic vesicles and bind to molecules of neurotransmitter. D. bind to ion channels on the neuron membrane and cause them to open for the transmitter.

B. bind to proteins on the surface of synaptic vesicles.

With damage to nerve fibers, larger distances between the site of damage and the target structure innervated result in _________ chances of successful regeneration. A. increased B. decreased

B. decreased

According to Ohm's law, current is A. directly related to both voltage and resistance. B. directly related to voltage and inversely related to resistance. C. inversely related to both voltage and resistance. D. indirectly related to voltage and directly related to resistance.

B. directly related to voltage and inversely related to resistance.

The type of neuronal circuit that spreads information from one presynaptic neuron to several postsynaptic neurons is a _____________ circuit. A. converging B. diverging C. reverberating D. parallel-after-discharge E. None of the choices is correct.

B. diverging

The nervous system controls the activity of muscles and glands. Muscles and glands can generate changes and are therefore called A. afferents. B. effectors. C. stimuli. D. visceral.

B. effectors.

The glial cell that helps to circulate cerebrospinal fluid is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

B. ependymal cell.

Potassium has a higher concentration A. inside the cell versus outside the cell, and sodium is also more concentrated inside versus outside the cell. B. inside the cell versus outside the cell, whereas sodium has a higher concentration outside versus inside the cell. C. outside the cell versus inside the cell, and sodium is also more concentrated outside versus inside the cell. D. outside the cell versus inside the cell, whereas sodium has a higher concentration inside versus outside the cell.

B. inside the cell versus outside the cell, whereas sodium has a higher concentration outside versus inside the cell.

A depolarization is when the inside of a neuron becomes _______________ the resting membrane potential. A. more negative than B. less negative than C. closer to

B. less negative than

In a myelinated axon, the greatest concentration of voltage-gated ion channels is in the A. myelinated regions. B. neurofibril nodes.

B. neurofibril nodes.

To measure the resting potential of a neuron, a physiologist would place A. two electrodes inside the neuron. B. one microelecrode inside the neuron and another in the interstitial fluid. C. one electrode inside the cell and another inside another cell. D. one electrode inside the cell and another outside the body.

B. one microelecrode inside the neuron and another in the interstitial fluid.

The cytoplasm within a cell body of a neuron is called the soma. perikaryon. neurokaryon. chromatophilic substance. chromatophobic substance.

B. perikaryon.

Nerves and ganglia are structures found in the A. central nervous system. B. peripheral nervous system. C. central and peripheral nervous systems.

B. peripheral nervous system.

In neurophysiology, the term "summation" refers to the addition of A. action potentials at the node of Ranvier. B. postsynaptic potentials at the initial segment. C. excitatory neurotransmitter molecules at a receptor. D. resting membrane potentials in a particular area of the brain. E. presynaptic hyperpolarizations.

B. postsynaptic potentials at the initial segment.

Most commonly, a synapse is made between a A. presynaptic neuron's dendrite and a postsynaptic membrane's cell body. B. presynaptic neuron's axon and a postsynaptic neuron's dendrite. C. presynaptic neuron's axon hillock and a postsynaptic neuron's cell body. D. presynaptic neuron's soma and a postsynaptic neuron's synaptic knob.

B. presynaptic neuron's axon and a postsynaptic neuron's dendrite.

Chemically gated ion channels are mainly found in the ________ segment of a neuron. A. initial B. receptive C. conductive D. transmissive

B. receptive

One of the ways in which neurotransmitter is removed from the synaptic cleft is A. endocytosis by the postsynaptic cell. B. reuptake by the presynaptic cell. C. phagocytosis by a macrophage. D. dendritic lassos.

B. reuptake by the presynaptic cell.

A mixed nerve is one that contains both A. cranial and spinal nerve fibers. B. sensory and motor neurons. C. unipolar and bipolar neurons. D. an endoneurium and an epineurium. E. presynaptic and postsynaptic neurons.

B. sensory and motor neurons.

The monoamine that has functions related to sleep, appetite, cognition, and mood is A. dopamine. B. serotonin. C. norepinephrine. D. acetylcholine. E. epinephrine.

B. serotonin.

Maintenance of appropriate ion concentrations (especially after nerve impulses that involved ion diffusion) is primarily the job of A. voltage-gated channels. B. sodium-potassium pumps. C. chemically gated channels. D. mechanically gated channels.

B. sodium-potassium pumps.

The portion of the nervous system that conducts impulses from the skin, joints, skeletal muscles, and special senses is the ___________ division. A. autonomic motor B. somatic sensory C. somatic motor D. visceral sensory

B. somatic sensory

As a neuron's refractory period ends, its sodium channels are changing from A. their resting state to their inactivated state. B. their inactivated state to their resting state. C. their resting state to their activated state. D. their activated state to their resting state.

B. their inactivated state to their resting state.

The type of voltage-gated channel that possesses an inactivation gate that temporarily closes after the channel is active is the A. voltage-gated potassium channel. B. voltage-gated sodium channel. C. voltage-gated calcium channel. D. voltage-gated chloride channel.

B. voltage-gated sodium channel.

The separation of oppositely charged ionic particles across a resting neuron's membrane results in a potential that is measured as a A. current. B. voltage. C. conductance. D. resistance.

B. voltage.

Which choice correctly orders the connective tissue wrappings of a nerve, beginning at the outermost layer? A. Perineurium → epineurium→ endoneurium B. Perineurium → endoneurium→ epineurium C. Epineurium → perineurium→ endoneurium D. Epineurium → endoneurium→ perineurium E. Endoneurium → perineurium→ epineurium

C. Epineurium → perineurium→ endoneurium

The primary inhibitory neurotransmitter in the brain is A. glutamate. B. valine. C. GABA. D. serotonin. E. serine.

C. GABA.

Which functional class of neurons lies entirely within the central nervous system? A. Bipolar neurons B. Sensory neurons C. Interneurons D. Unipolar neurons E. Motor neurons

C. Interneurons

Which part of the neuron contains the nucleus? Dendrite Axon Soma Axon hillock Telodendrion

C. Soma

What do all glial cells have in common? A. They help to transmit the nerve signals. B. They transfer blood to the various neurons. C. They assist neurons in their respective functions. D. They all attack pathogens. E. They absorb extra blood and cerebrospinal fluid.

C. They assist neurons in their respective functions.

Which is not a function of the motor division of the nervous system? A. Conducts impulses from the CNS B. Transmits impulses to muscles and glands C. Transmits impulses from the viscera D. Voluntary control of skeletal muscle E. Involuntary control of the heart

C. Transmits impulses from the viscera

When a nerve impulse reaches the transmissive segment of a neuron, A. calcium is pumped into the neuron and neurotransmitter diffuses out through channels. B. calcium is released from the neuron along with neurotransmitter from synaptic vesicles. C. calcium diffuses into the neuron and neurotransmitter is released by exocytosis. D. calcium and neurotransmitter diffuse into the synaptic knob. E. calcium is immediately pumped out of the neuron and vesicles of neurotransmitter undergo phagocytosis.

C. calcium diffuses into the neuron and neurotransmitter is released by exocytosis.

Receptors are parts of the nervous system that allow it to A. initiate responses to information. B. process information. C. collect information. D. conduct impulses to muscles.

C. collect information.

The epineurium is composed of A. dense regular connective tissue. B. simple squamous epithelium. C. dense irregular connective tissue. D. areolar connective tissue. E. pseudostratified nonkeratinized epithelium.

C. dense irregular connective tissue.

Electrical synapses involve coupling of neurons by A. synaptic clefts. B. desmosomes. C. gap junctions. D. satellite cells.

C. gap junctions.

Catecholamines are a subtype of __________ neurotransmitter. A. acetylcholine B. neuropeptide C. monoamine D. amino acid E. soluble gas

C. monoamine

A nerve impulse travels fastest along ________ axons of ______ diameter. A. myelinated, small B. unmyelinated, small C. myelinated, large D. unmyelinated, large

C. myelinated, large

The glial cell that myelinates and insulates axons in the peripheral nervous system is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

C. neurolemmocyte.

A bipolar neurons has A. two axons extending from the cell body. B. two dendrites extending from the cell body. C. one axon and one dendrite extending from the cell body. D. a single short process that extends from the cell body and E. then splits into a peripheral and a central branch.

C. one axon and one dendrite extending from the cell body.

The hyperpolarization that occurs at the end of an action potential is due to the prolonged A. open state of voltage-gated sodium channels. B. closure of chemically gated sodium channels. C. open state of voltage-gated potassium channels. D. closure of voltage-gated potassium channels. E. open state of chemically gated sodium channels.

C. open state of voltage-gated potassium channels.

The connective tissue wrapping that surrounds bundles (fascicles) of axons is the A. epineurium. B. endoneurium. C. perineurium. D. endosteum. E. periosteum.

C. perineurium.

Billions of CNS interneurons are grouped in complex patterns called neuronal A. networks. B. complexes. C. pools. D. meshes. E. webs.

C. pools.

The function of myelin is to A. block the transmission of a nerve impulse. B. provide points of attachment for nerve threads. C. produce faster nerve impulse propagation. D. produce slow but continuous impulse conduction.

C. produce faster nerve impulse propagation.

The type of neuronal circuit that ensures that we continue to breathe while asleep is a _____________ circuit. A. converging B. diverging C. reverberating D. parallel-after-discharge E. None of the choices is correct.

C. reverberating

The type of neuronal circuit that uses feedback to produce a repeated, cyclical stimulation of the circuit is a _____________ circuit. A. converging B. diverging C. reverberating D. parallel-after-discharge E. None of the choices is correct.

C. reverberating

Following damage to axons nearby, oligodendrocytes A. secrete growth factors. B. do not secrete any chemicals. C. secrete growth-inhibitory molecules. D. grow their own fibers to occupy the space.

C. secrete growth-inhibitory molecules.

The portion of the nervous system that has voluntary control over skeletal muscles is the _____________ division. autonomic motor somatic sensory somatic motor visceral sensory

C. somatic motor

When multiple presynaptic neurons release neurotransmitter at various locations onto the postsynaptic neuron at the same time, this results in A. suprathreshold hyperpolarization. B. temporal summation. C. spatial summation. D. several action potentials.

C. spatial summation.

The electrochemical gradient refers to A. the difference in concentration of a substance between two areas. B. the difference in electrical charge between two areas. C. the combination of electrical and chemical gradients between two areas. D. the resistance a membrane has to allowing any charged chemical to pass through it.

C. the combination of electrical and chemical gradients between two areas.

Continuous conduction of a nerve impulse occurs only along A. myelinated axons. B. dendrites. C. unmyelinated axons. D. axons in the PNS. E. axons in the CNS.

C. unmyelinated axons.

A graded potential is one that A. is all or none (always the same intensity). B. travels the length of the nerve fiber (is long-distance). C. varies in size depending on the magnitude of the stimulus (larger voltage change for stronger stimulus). D. lasts for several seconds after ion channels have opened, closed, and reset.

C. varies in size depending on the magnitude of the stimulus (larger voltage change for stronger stimulus).

There are two types of synapses, based on mode of communication. What are they? A. Mechanical and chemical B. Magnetic and physical C. Physical and chemical D. Chemical and electrical E. Mechanical and electrical

D. Chemical and electrical

Which is true regarding the action of a neurolemmocyte? A. Each neurolemmocyte can form a myelin sheath around many axons simultaneously. B. A neurolemmocyte is responsible for forming part of the blood-brain barrier. C. Neurolemmocytes function only within the CNS. D. Each neurolemmocyte can wrap only a 1 mm portion of a single axon. E. A neurolemmocyte attacks pathogens.

D. Each neurolemmocyte can wrap only a 1 mm portion of a single axon.

When a neurotransmitter causes the opening of chemically gated potassium channels on the postsynaptic cell, the postsynaptic potential that results is an A. EPSP, which is a depolarization. B. EPSP, which is a hyperpolarization C. IPSP, which is a depolarization. D. IPSP, which is a hyperpolarization.

D. IPSP, which is a hyperpolarization.

What structures extend into the axon and dendrite of a neuron to provide tensile strength? Motor filaments Nissl bodies Telodendria Neurofibrils Collateral fibers

D. Neurofibrils

What type of circuit would you use to solve a higher-order mathematical problem? A. Converging B. Diverging C. Reverberating D. Parallel-after-discharge E. None of the choices is correct.

D. Parallel-after-discharge

Choose the answer that correctly lists, in chronological order, the events involved in synaptic transmission. a: A nerve impulse reaches the synaptic knob. b: Neurotransmitter molecules diffuse across the synaptic cleft. c: A nerve impulse begins in the postsynaptic cell. d: Neurotransmitter molecules bind to receptors in the postsynaptic cell. e: A voltage change occurs in the postsynaptic cell. A. a, c, b, d, e B. a, b, e, d, c C. c, b, d, e, a D. a, b, d, e, c E. c, a, b, d, e

D. a, b, d, e, c

The endoneurium is composed of A. dense regular connective tissue. B. simple squamous epithelium. C. dense irregular connective tissue. D. areolar connective tissue. E. pseudostratified nonkeratinized epithelium.

D. areolar connective tissue.

Neural stem cells in the CNS A. have no known function. B. can only form glial cells. C. can form new neurons throughout the CNS. D. can form new neurons in only certain portions of the CNS such as the hippocampus. E. can migrate to the PNS as needed.

D. can form new neurons in only certain portions of the CNS such as the hippocampus.

The glial cell that defends the body against pathogens is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

D. microglial cell.

The type of neuronal circuit in which several neurons process the same information at one time is a _____________ circuit. A. converging B. diverging C. reverberating D. parallel-after-discharge E. None of the choices is correct.

D. parallel-after-discharge

As an axon approaches the cell onto which it will terminate, it generally branches repeatedly into several A. teloaxons. B. dendrites. C. collateral axons. D. telodendria. E. neurolemmocytes.

D. telodendria.

A neuron conducting an impulse from the stomach wall to the CNS would be classified as a(n) __________ neuron. autonomic motor somatic sensory somatic motor visceral sensory

D. visceral sensory

Typically, the resting membrane potential of a neuron is A. 7 V. B. 700 mV. C. −7 V. D. −70 mV. E. 0 mV.

D. −70 mV.

Of the two types of synapses, based on mode of communication, which is less common but allows faster signal transmission? A. Chemical synapse B. Mechanical synapse C. Physical synapse D. Magnetic synapse E. Electrical synapse

E. Electrical synapse

Fast axonal transport is passive and only occurs in the anterograde direction. passive and only occurs in the retrograde direction. active (requires ATP) and only occurs in the anterograde direction. active (requires ATP) and only occurs in the retrograde direction. active (requires ATP) and can occur in either the anterograde or retrograde direction.

E. active (requires ATP) and can occur in either the anterograde or retrograde direction.

Based on function, the vast majority of neurons are A. sensory neurons. B. motor neurons. C. unipolar neurons. D. bipolar neurons. E. interneurons.

E. interneurons.

A nerve A. contains a single axon. B. is found only in the CNS. C. carries only sensory information. D. carries information only toward the PNS. E. is a cablelike bundle of parallel axons.

E. is a cablelike bundle of parallel axons.

The glial cell that myelinates and insulates axons within the CNS is the A. astrocyte. B. ependymal cell. C. neurolemmocyte. D. microglial cell. E. oligodendrocyte.

E. oligodendrocyte.

The afferent division of the nervous system is also known as the _____ division. A. motor B. cranial C. ganglial D. efferent E. sensory

E. sensory

The neurons that are responsible for integrating information by retrieving, processing, storing, and "deciding" how the body responds to stimuli are sensory neurons. motor neurons. accessory neurons. correlation neurons. interneurons.

interneurons.