Deck 2: Neurophysiology

Question 1

What is the name of the portion of the sensory neuron that is easily excited and has the most negative action potential threshold?

A) Dendritic zone
B) Soma
C) Axon hillock
D) Output zone

Answer 1

Axon hillock

Question 2

A local anesthetic is said to cause a loss of nociception.What does this mean?

A) A loss of pain
B) A loss of polarization
C) A loss of muscle mobility
D) A loss of cell membrane potential

Answer 2

A loss of pain

Question 3

What are the nerves that conduct signals away from the brain or spinal cord called?

A) Neurotransmitters
B) Electrical synapses
C) Afferent nerves
D) Efferent nerves

Answer 3

Efferent nerves

Question 4

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The electrical potential of the neuron is approximately -70 mV.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 5

What is the propagation of action potentials along myelinated axons from one node of Ranvier to another called?

A) Nonmyelinated
B) Saltatory conduction
C) Polarization
D) Refractory period

Question 6

Tasks for neurons include receiving,processing,and sending information.They communicate with other neurons through axons and synapses.

A) Both statements are true.
B) Both statements are false.
C) The first statement is true; the second statement is false.
D) The first statement is false; the second statement is true.

Question 7

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The impulse moves between the uninsulated nodes of Ranvier that exist between each Schwann cell.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 8

The lipoprotein sheath that surrounds many neurons is called ______ and is composed of ______.

A) Lipid; oligodendrocytes
B) Myelin sheath; Schwann cells
C) Nodes of Ranvier; Schwann cells
D) White fibers; oligodendrocytes

Question 9

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
During this stage,the second action potential is inhibited but not impossible should a larger stimulus be applied.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 10

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The nerve is stimulated by the minimal threshold level.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 11

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The gated Na⁺ channels on the resting neuron's membrane release and open suddenly in order to allow the Na⁺ in the extracellular fluid to influx into the cell.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 12

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
Occurs once the peak of the action potential is reached and the membrane potential begins to move back toward the resting potential.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 13

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The interval during which a second action potential cannot be initiated,no matter how large a stimulus is applied.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 14

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
During this stage,the electrical charge on the outside of the membrane is positive,while the electrical charge on the inside of the membrane is negative.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 15

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The outside of the cell contains excess sodium ions at a ratio of 14:1; the inside of the cell contains excess potassium ions.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 16

What is the most distal arborization of the nerve endings called?

A) Dendritic zone
B) Soma
C) Axon hillock
D) Output zone

Question 17

What are the endogenous chemicals that transmit signals from a neuron to a target cell across a synapse called?

A) Neurotransmitters
B) Electrical synapses
C) Afferent nerves
D) Efferent nerves

Question 18

MATCHING
Match each description with the term that correctly identifies the generation and conduction of the nerve impulse stage. Terms may be used more than once.
The resting potential of the cell changes to become more negative,but not enough to trigger the firing threshold.

A)Polarization
B)Slow depolarization
C)Rapid depolarization
D)Repolarization
E)Relative refractory period
F)Absolute refractory period

Question 19

What are the nerves that conduct signals from sensory neurons to the spinal cord or brain called?

A) Neurotransmitters
B) Electrical synapses
C) Afferent nerves
D) Efferent nerves

Question 20

What is another name for axons?

A) Core bundles
B) Mantle bundles
C) Nerve fibers
D) All of the above

Question 21

The nerve cell stage in which potassium returns to the inside of the cell and sodium returns to the outside of the cell is called what?

A) All-or-none principle
B) Polarization
C) Depolarization
D) Refractory period

Question 22

The cell body of which neuron participates in impulse conduction and therefore is located at the terminal arborization?

A) Sensory neurons
B) Motor neurons
C) Somatic neurons
D) All of the above

Question 23

What is the layer of connective tissue that surrounds each axon within a nerve called?

A) Epineurium
B) Endoneurium
C) Perineurium
D) Fascicle

Question 24

Nerve fiber type _____ ,the largest nerve fiber with the fastest conduction velocity,is responsible for what type of pain?

A) A alpha; pain related to temperature
B) A delta; sharp pain
C) B; touch and pressure pain
D) C; dull, aching pain

Question 25

The main difference between motor neurons and sensory neurons is the location of which body part?

A) Axon
B) Dendritic zone
C) Cell body
D) Terminal arborization

Question 26

At the synaptic knobs of neuron cells,what type of action is required to have the electrical impulse cross the synapse of one cell to another cell?

A) The action of electrical synapses
B) The action of chemical synapses
C) The action of either electrical or chemical synapses
D) Repolarization

Question 27

What is the layer of connective tissue that surrounds the entire nerve called?

A) Epineurium
B) Endoneurium
C) Perineurium
D) Fascicle

Question 28

Which description best describes the mechanism by which local anesthetic drugs work?

A) Anesthetic drugs bind to the sodium channels, the influx of sodium is interrupted, the action potential cannot rise, and the signal conduction is inhibited.
B) Anesthetic drugs bind to the potassium channels, the influx of sodium is interrupted, the action potential cannot rise, and the signal conduction is inhibited.
C) Anesthetic drugs bind to the sodium channels, the influx of potassium is interrupted, the action potential cannot rise, and the signal conduction is inhibited.
D) Anesthetic drugs bind to the sodium channels, the influx of sodium and potassium is interrupted, the action potential cannot rise, and the signal conduction is inhibited.

Question 29

The difference between the electrical charge on the outside of the cell and that on the inside of the cell is called what?

A) Firing threshold
B) Membrane potential
C) Polarization
D) Action potential

Question 30

Why do the IA and PSA require more anesthetic than an infiltration of local anesthetic?

A) The locations for injecting the IA and PSA are more posterior than anterior.
B) The diameter of the nerve fiber is larger for the IA and PSA.
C) The nerve fibers are unmyelinated.
D) All of the above

Question 31

Nerve fiber type _____ ,the smallest and the most numerous nerve fiber,is responsible for what type of pain?

A) A alpha; pain related to temperature
B) A delta; sharp pain
C) B; touch and pressure pain
D) C; dull, aching pain

Question 32

As the action potential moves down the line,its strength decreases as it moves from one neuron to the next.The action potential in myelinated axons does not propagate as waves as in unmyelinated axons.

A) Both statements are true.
B) Both statements are false.
C) The first statement is true; the second statement is false.
D) The first statement is false; the second statement is true.

Question 33

What do local anesthetic drugs inhibit in order to prevent nerve cell stimulation?

A) Sodium influx
B) Potassium influx
C) Chloride excretion
D) All of the above