Exam 4 #2 Flashcards by Athziry Rodriguez

If you experimentally increase the permeability of an axonal membrane to sodium ions, the resting membrane potential for the neuron will

Increase because the influx of sodium depolarizes the neuron
decrease because the influx of sodium depolarizes the neuron
decrease because the efflux of potassium that follows sodium influx repolarizes the membrane
remain unchanged

Increase because the influx of sodium depolarizes the neuron

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Neurotransmitters are stored in the

sarcoplasmic reticulum
intercalated disc
synaptic vesicles
neurotransmitters are not stored but they are free floating in the extracellular space

neurotransmitters are not stored but they are free floating in the extracellular space

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Which of the following neurons forms the blood-brain barrier?

astrocyte
microglial cell
oligodendrocytes
ependymal cell
none of the above

None of the above

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The Nat-K* ATPase pump

pumps three sodium inside the cell and two potassium ions outside
pumps two sodium ions outside the cell and three potassium ions inside
pumps an equal ration of sodium and potassium against its concentration gradient
pumps three sodium ions to the outside the cell and two potassium ions to the inside

pumps three sodium ions to the outside the cell and two potassium ions to the inside

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During depolarization

sodium ions move rapidly out of the cell
potassium ions move rapidly out of the cell
sodium ions move rapidly into the cell
potassium ions move rapidly into the cell

sodium ions move rapidly into the cell

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Decreasing the diameter of an'axon will results in
a decrease in the conduction velocity
an increase in the conduction velocity
no change in the conduction velocity
none of the above

a decrease in the conduction velocity

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A resting membrane potential is -70 mV and the threshold is determined to be -60 mV. A change in membrane potential to -52 mV will results in

depolarization
hyperpolarization
an action potential
repolarization

An action potential

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Endocytosis of neurotransmitters into the synaptic cleft is dependent upon

Ca2+ efflux
Ca2t influx
Active transport of Ca2+ into the cell
None of the above

None of the above

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The absolute refractory period is defined as
a point where Nat channels begin to inactivate and the K+ channels are still activatine

the point where the Nat current is equal and opposite the K+ current

the point where an action potential cannot be evoked, regardless of the stimulus strength

the point where an action potential can only be evoked by a stronger then normal stimulus

the point where an action potential cannot be evoked, regardless of the stimulus strength

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A neural tissue has a resting membrane potential of -75 mV. Closing the K+ voltage gated channels will most likely result in

depolarization
repolarization
hyperpolarization
initiation of an action potential
no change in membrane potential

Depolarization

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Inhibitory postsynaptic potentials (IPSPs)

result in local depolarization
result in local hyperpolarization
result in local repolarization
increase membrane permeability to sodium ions
prevent the efflux of calcium ions

Result in local hyperpolarization

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The resting membrane potential of a cardiac cell is -70 mV. An influx of [Ca2*] will

make the cell more excitable
make the cell less excitable
no effect on resting membrane potential
calcium cannot influx, it can only efflux

Make the cell more excitable

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Neurotransmitters are released into the synaptic cleft and bind to

presynaptic terminal
the synaptic knob receptors
calcium ions
receptors on the postsynaptic membrane

receptors on the postsynaptic membrane

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A slight shift away from the resting membrane potential is termed

membrane potential
resting membrane potential
local or graded potential
action potential

Local or graded potential

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When an action potential reaches the axonal bulb

the pre and postsynaptic neurons come in direct contact
the nerve impulse will pass in either direction
an electrical spark will jump the gap
chemical transmitters are released

chemical transmitters are released

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Which of the following fiber types would one expect to have the greatest rate of impulse conduction?

type A fiber
type B fiber
type C fiber
type D fiber

Type A fiber

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At resting membrane potential, which of the following ions leak “freely” through the membrane channels?

N+
K+
Ca?t
CI

K+

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Which of the following neurotransmitters is inhibitory in function?

Acetylcholine
Substance P
Norepinephrine
Glycine
All of the above neurotransmitters are excitatory in action

Glycine

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An increase in extracellular (Ca2*] will result in
depolarization
repolarization
hyperpolarization
no physiological effect on resting membrane potential

no physiological effect on resting membrane potential

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An inhibitory neurotransmitter is released into the synaptic cleft. Which of the following channels will most likely be stimulated to open?
Sodium and potassium channels
Potassium and/or chioride channels
Sodium and chloride channels
Only the sodium channels

Potassium and/or chloride channels

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The resting membrane potential for a typical cardiac cell is -60 mV. Changing the resting membrane potertial to -70 mV will result in

depolarization
repolarization
hyperpolarization
no effect on resting membrane potential since calcium is the primary ion for the initiation of an action potential for a typical contracting cardiomyopathy

Hyperpolarization

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The resting membrane potential for a sensory neuron is -80 mV. Increasing the extracellular [Nat] will result in

a local potential
an increase in the amplitude of the action potential spike
a decrease in the amplitude of the action potential spike
hyperpolarization
repolarization

an increase in the amplitude of the action potential spike

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The resting membrane potential for a motor neuron axon is -90 mV. An influx of chloride ions (CI) will catse the resting
membrane potential to

become more excitable
become less excitable
remain at -90 mV
depolarize

Become less excitable

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Transmission of nerve impulses across a synaptic cleft is mediated by

sodium ions
potassium ions
neurotransmitters
the node of Ranvier

neurotransmitters

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All the following statements are correct for myelin sheath EXCEPT It is associated with white fibers (matter) in the brain It is important in nerve conduction velocity It covers cell bodies in the brain and spinal cord It is destroyed in multiple sclerosis

It covers cell bodies in the brain and spinal cord

The resting membrane potential for a motor neuron is -90 mV. Decreasing the extracellular [K*] will cause the neuron to become more excitable less excitable repolarize no change in the resting membrane potential

Less excitable

A neuron is said to be polarized because the action potential can travel in a bilateral direction the soma is always at one extremity of the cell there is a difference of electrical potential across its membrane it tends to cluster with other neurons in nuclei.

there is a difference of electrical potential across its membrane

All the following statements regarding acetylcholine and the activities occurring at the cholinergic synapse are correct EXCEPT calcium ions influx into an axonal terminal stimulates the release of ACh from vesicles ACh is stimulatory to skeletal muscle causing depolarization ACh is inhibitory in cardiac muscle causing hyperpolarization Excess ACh is removed by acetylcholineesterase in the synaptic cleft ACh moves from the post synaptic neuron to the presynaptic neuron

ACh moves from the post synaptic neuron to the presynaptic neuron

The resistance across the cell membrane is determined by ``` the thickness of the membrane the amount of lipid in the membrane the surface area of the membrane the number of type of channels In the membrane the axoplasmic flow ```

the number of type of channels In the membrane

The primary determinant of the resting membrane potential is the membrane permeability and influx of sodium the membrane permeability and influx of potassium the negative charge of the interstitial fluid the positively charged cellular cytoplasm none of the above

None of the above

An increased in extracellular [K*] will cause the neuron to depolarize repolarize hyperpolarize none of the above

Depolarize

The relative refractory period is defined as a point where Na* channels begin to inactivate and the K* channels are still activating the point where the Na* current is equal and opposite the K* current the point where an action potential cannot be evoked, regardless of the stimulus strength the point where an action potential can only be evoked by a stronger the normal stimulus

the point where an action potential can only be evoked by a stronger the normal stimulus

Excitatory postsynaptic potentials (EPSPs) result in local depolarization result in local hyperpolarization result in local repolarization increase membrane permeability to potassium ions decreased membrane permeability to calcium ions

result in local depolarization

``` The ulna nerve is covered by the: endoneurium perineurium epineurium macroneurum ```

epineurium

An inhibitory neurotransmitter is released into the synaptic cleft. Which of the following channels will most likely be stimulated to open? Sodium and potassium channels Potassium and/or chloride channels Sodium and chloride channels Oniv the sodium channels

Potassium and/or chloride channels

The cellular loss of positive ions such as potassium from a resting neuron causes the neuron to become less negative depolarization Hyperpolarization The cellular loss of positive ions such as potassium from a resting neuron causes The threshold to be reached with a resulting action potential Only A& C

Hyperpolarization

If a neurotransmitter binds to receptor molecules that open K* ion channels, the result is ``` an excitatory postsynaptic potential an inhibitory postsynaptic potential Local depolarization increased permeability of presynaptic membrane to Ca?+ ions temporal summation ```

an inhibitory postsynaptic potential

The difference between sodium and potassium in the generation of action potential is: Sodium causes repolarization while potassium causes depolarization Sodium causes unipolarization while potassium causes repolarization Sodium causes repolarization while potassium is not required in the action potential mechanism Sodium causes depolarization while potassium causes repolarization None of the above

Sodium causes depolarization while potassium causes repolarization

Which of the following statements is most correct for saltatory conduction? The action potentials move in all directions along an axon The action potentials occur at successive nodes along the length of the stimulated axon The local currents depolarize adjacent areas of membrane so that action potentials continue to form along the membrane All the above None of the above

The action potentials occur at successive nodes along the length of the stimulated axon

Lesions on a bundle of myelinated fibers will most likely result in Nerve conduction would be enhanced with an increase in motor coordination There would be no side effects of this type of lesion Nerve conduction would be impaired and weakness, loss of coordination, and visual impairment would occur Nerve conduction would be impaired but complete regeneration will ensue None of the above

Nerve conduction would be impaired and weakness, loss of coordination, and visual impairment would occur

A 65-year-old recently diagnosed with cerebral vascular accident, i.e., stroke. As a direct result from the stroke, some of the neural tissues were damaged. What type of neuroglia would you expect to find at the site of injury and is involved in scar formation? ``` Astrocytes Satellite cells Ependymal cells Microgila Oligodendrocytes ```

Astrocytes

Which of the following groove is found between the frontal and parietal lobes? Central sulcus of Rolando Lateral suícus of Sylvius Transverse fissure Sagittal sinus of Galen

Central sulcus of Rolando

``` The central sulcus separates the ___ from the ____ lobe Temporal/occipital Frontal/parietal Parietal/occipital Temporal/frontal Frontal/occipital ```

Frontal/parietal

The ability to think and solve problems resides in which area of the cerebrum? ``` Frontal Parietal Occipital Temporal Insula ```

Frontal

The primary somatosensory cortex is located in the ``` Frontal lobe Precentral gyrus Parietal lobe Occipital lobe Temporal lobe ```

Parietal lobe

The cerebellum functions in The planning and coordination of movement Learning, memory, and personality Biological rhythms Homeostatic functions such as breathing and heart rate None of the above

The planning and coordination of movement

Bundles of white matter in the cerebrum are known as ``` Arbor vitae Ganglia Tracts Nuclei Myelinated axons ```

Tracts

What are the three primary brain vesicles that form from the neural tube? Mesencephalon, telencephalon, diencephalon Forebrain, midbrain, hindbrain Telencephalon, myelencephalon, mesencephalon Cerebrum, thalamus, cerebellum Midbrain, pons, medulla

Forebrain, midbrain, hindbrain

The primary motor cortex of the right hemisphere Controls the motor activity on the left side of the body Receives and processes sensory input Integrates senses from multiple different sources Controls motor activity on the right side of the body Involved in proprioception

Controls the motor activity on the left side of the body

What is the most likely result when the corpus callosum is transected? communication between a cerebral cortex in one hemisphere with other areas of the same hemisphere would be impaired communication between the brain and spinal cord would be impaired communication within a single brain hemisphere would be impaired communication between the right and left cerebral hemispheres would be impaired none of the above

communication between the right and left cerebral hemispheres would be impaired

Cerebrospinal fluid (SF) in the third ventricle will drain/flow into the ``` Lateral ventricles Fourth ventricles Choroid plexus Dural sinua Subarachnoid space ```

Fourth ventricles

``` Which of the following structures carries information from the brain? Posterior column Dorsal column medial lemniscus Spinocerebellar tract Anterolateral system Corticospinal tract ```

Corticospinal tract

Where is the sensation of touch processed? ``` Prefrontal cortex Primary motor cortex Primary somatosensory cortex Somatosensory association area/cortex Cerebellum ```

Primary somatosensory cortex

What part of the cerebral cortex is responsible for personality, the creation of an awareness of self, and the ability to recognize appropriate behavior? ``` Parietal association area Wernicke's area Prefrontal cortex Basal nuclei None of the above ```

Prefrontal cortex

Visual stimuli that arrive in the thalamus are relayed to the Primary visual cortex in the frontal lobe Primary visual cortex in the occipital lobe Medulla Brainstem nuciel Reticular systen

Primary visual cortex in the occipital lobe

The pineal gland, and endocrine structure that secretes the hormone melatonin, is found in the ``` Cerebrum Diencephalon Midbrain Brain stem Hindbrain ```

Diencephalon

``` The right and left cerebral hemispheres are connected by Association fibers Commissural fibers Projection fibers Directional fibers All the above ```

Commissural fibers

Which of the following statements is most correct? Tracts are unmyelinated axons located in the PNS swered White matter of the brain is located peripherally Nuclei are collection of nerve cell bodies Ganglion are collection of myelinated axons Arbor vitae represent gray matter in the cerebellum

Nuclei are collection of nerve cell bodies

The ______ contains centers for heartbeat, breathing, and blood pressure. ``` cerebellum cerebrum spinal cord rect! brain stem ```

brain stem

``` are axons which connect the corresponding gray areas of the two brain hemispheres. Most pass through (and form) the ____ Projection fibers, corpus callosum Commissural fibers, corpus callosum Association fibers, basal nuclei Basal fibers, basal ganglia Substantia nigra, Broca's area ```

Commissural fibers, corpus callosum

Collectively and functionally, the ____ are called the brain stem. ``` midbrain, pons medulla cerebellum onlv A. B. & C ```

Only A. B. C

``` Nerve fibers carrying signals from the CNS to the PNS are called.___ or ___ fibers Afferent, sensory Afferent, motor Motor, efferent Efferent, afferent All of the above ```

Motor, efferent

The brain and spinal cord make up the ____ nervous system. All other nerves are part of the _____ nervous system. ``` Central, peripheral Peripheral, central Autonomic, somatic Somatic, autonomic Sympathetic, parasympathetic ```

Central, peripheral

In the CNS, ____ are cells which line the fluid-filled cavities, and which secrete, transport, and circulate the fluid surrounding the brain and spinal CNS ``` Astrocytes Microglias, Ependymal Oligodendrocytes Schwann cells ```

Ependymal

``` The rough endoplasmic reticulum in neurons are called Organelles Nissl bodies Golgi bodies Cajal bodies neurotransmitters ```

Nissl bodies

is a collection of neuronal cell bodies located inside of the CNS. ``` Nucleus Ganglion Nerve Tract None of the above ```

Nucleus

``` A ______ is a collection of neuronal axons, blood vessels, and connective tissues in the PNS. Nucleus Ganglion Nerve Tract None of the above ```

Nerve

The folds and convolutions of the, cerebral hemispheres are namèd for their three-dimensional form. The ridges are called ``` Gyri Sulci Fissures Ventricles ) Mater ```

Gyri

The folds and convolutions of the cerebral hemispheres are named for their three-dimensional form. The shallow grooves are called ``` Gyri Fissures Mater Sulci Ventricles ```

Sulci

The resting membrane potential arises because a fast Na+ channel opens transiently, allowing Na+ to flow down its osmotic gradient the chemical gradient is equal to the electrical gradient the is an asymmetric distribution of sodium and potassium ions there can be no separation of ions in solution all of the above

the is an asymmetric distribution of sodium and potassium ions

``` A neural tissue has a resting membrane potential of -75 mV. Opening the K* channels will most likely result in depolarization repolarization hyperpolarization initiation of an action potential no change in membrane potential ```

hyperpolarization

Depolarization of an excitable membrane will shift the membrane potential towards Minus ninety mV (-90 mV) Minus eighty-five mV (-85 mV) Minus seventy mV (-70 mV) Zero (0)

Zero 0

Nodes of Ranvier are Interruptions in the myelin sheath along the course of a myelinated axon Collections of immune cells in the CNS Satellite cells that support neuron cell bodies in ganglia Gaps between choroid plexuses where cerebral spinal fluid emerges None of the above

Gaps between choroid plexuses where cerebral spinal fluid emerges

The threshold of a neuron is the Total amount of neurotransmitter. it takes to cause an action potential Voltage that triggers activation of voltage-gated channels Time between binding of the neurotransmitter and firing of an action potential Voltage that triggers activatic gated channels. You selectec Voltage across the resting cell membrane

Voltage that triggers activation of voltage-gated channels

Exam 4 #2 Flashcards

(74 cards)