Question 1

The basic function of a neuron is to
A) transmit nutrients.
B) maintain dynamic equilibrium between glial cells and potassium ions.
C) communicate.
D) none of the above.

Accepted Answer

Neurons are specialized cells in the nervous system whose primary function is to communicate information throughout the body via electrical and chemical signals.

Question 2

Neurotransmitter substance
A) leaves the presynaptic neuron, activates ion channels, and enters the postsynaptic neuron.
B) leaves the presynaptic neuron, activates ion channels, and then is reabsorbed into the presynaptic neuron.
C) leaves the presynaptic neuron, activates ion channels, and then is absorbed into the lymphatic system.
D) leaves the postsynaptic neuron, activates ion channels, and then is absorbed into the presynaptic neuron.

Accepted Answer

Neurotransmitters are released from the presynaptic neuron, activate ion channels on the postsynaptic neuron, and are often reabsorbed by the presynaptic neuron through a process called reuptake.

Question 3

An action potential is
A) the return to baseline voltage that occurs following depolarization.
B) a change in electrical potential that occurs when the cell membrane is stimulated adequately to permit ion exchange between intra- and extracellular spaces.
C) the threshold phenomenon associated with movement in muscle.
D) none of the above.

Accepted Answer

An action potential is a rapid change in electrical potential across a cell membrane, occurring when a neuron or muscle cell is stimulated, allowing ions to move across the membrane.

Question 4

EPSP refers to
A) excitatory presummative potential.
B) excitatory perisynaptic potential.
C) excitatory presynaptic potential.
D) excitatory postsynaptic potential.

Accepted Answer

EPSP stands for excitatory postsynaptic potential, which is a postsynaptic potential that makes the neuron more likely to fire an action potential.

Question 5

The molecular "fuel" for active transport is
A) adenosine triphosphate (ATP).
B) monosodium glutamate (MSG).
C) lysergic acid diethylamine (LSD).
D) acetylcholinesterase (ACHE).

Accepted Answer

Adenosine triphosphate (ATP) provides the energy required for active transport processes in cells, as it releases energy when its phosphate bonds are broken.

Question 6

Myelinated fibers conduct the wave of depolarization more rapidly than demyelinated fibers
A) because the lipids that make up myelin are hydrophobic in nature.
B) primarily due to saltatory conduction.
C) because myelin serves as an electrical conductor.
D) because depolarization occurs before hyperpolarization.

Accepted Answer

Myelinated fibers conduct impulses more rapidly due to saltatory conduction, where the action potential jumps from one node of Ranvier to the next, bypassing the myelinated sections of the axon.

Question 7

In biological systems, voltage is the product of
A) ion movement.
B) myelin.
C) Schwann cells.
D) the neurotransmitter.

Accepted Answer

Voltage in biological systems is primarily generated by the movement of ions across cell membranes, creating an electrical potential difference.

Question 8

Voltage-sensitive proteins
A) are responsive to presence of voltage in their environment.
B) change shape and open in the presence of voltage in their environment.
C) a & b
D) none of the above.

Accepted Answer

Voltage-sensitive proteins respond to voltage changes in their environment by changing shape, which often results in the opening of channels or other functional changes.

Question 9

Excitation causes
A) depolarization.
B) hyperpolarization.
C) repolarization.
D) none of the above.

Accepted Answer

Excitation typically causes depolarization, which is a decrease in the membrane potential making the inside of the cell less negative compared to the outside.

Question 10

Electroencephalographic (EEG) recordings are actually records of A) motor end plates. B) action potentials. C) K⁺ ions. D) none of the above.

Accepted Answer

EEG recordings measure electrical activity in the brain, which is primarily due to action potentials generated by neurons.

Question 11

IPSP refers to
A) a potential that is excitatory in nature.
B) use of the neurotransmitter acetylcholine (ACH).
C) an inhibitory potential.
D) an input potential.

Accepted Answer

IPSP stands for Inhibitory Postsynaptic Potential, which is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.

Question 12

Communication between two neurons occurs at the
A) mitochondria.
B) protein shell.
C) nodes of Ranvier.
D) synapse.

Accepted Answer

Communication between two neurons occurs at the synapse, which is the junction where the axon terminal of one neuron meets the dendrite of another neuron, allowing for the transmission of signals.

Question 13

A neuron can fire approximately once every
A) 1 ms.
B) 10 ms.
C) 100 ms.
D) 1,000 ms.

Accepted Answer

The answer of A neuron can fire approximately once every
A)...

Question 14

Active cellular transport
A) is required to adjust the ion balance between intra- and extracellular environments.
B) involves the use of sodium-potassium pumps.
C) moves sodium out of the cell.
D) all of the above.

Accepted Answer

Active cellular transport is required to adjust the ion balance between intra- and extracellular environments, involves the use of sodium-potassium pumps, and moves sodium out of the cell.

Question 15

Because an action potential always results in the same neural response,
A) the neuron can only fire during inhibition.
B) the neuron cannot be used to differentiate stimuli.
C) the neuron is capable of representing differences in input only through rate of response.
D) none of the above.

Accepted Answer

The neuron represents differences in input through the frequency or rate of action potentials, not through the size or shape of the action potential itself, which is always the same.

Question 16

An action potential causes
A) synaptic vesicles to migrate to the synaptic membrane.
B) neurotransmitter to be released into the synaptic cleft.
C) a & b
D) none of the above.

Accepted Answer

An action potential triggers synaptic vesicles to move to the synaptic membrane and release neurotransmitters into the synaptic cleft.

Question 17

Adenosine triphosphate is a direct product of
A) the synaptic dyad.
B) gamma aminobutyric acid (GABA).
C) cellular mitochondria.
D) deoxyribonucleic acid (DNA).

Accepted Answer

Adenosine triphosphate (ATP) is produced in the mitochondria of cells through processes like oxidative phosphorylation and the citric acid cycle.

Question 18

The period following depolarization when a neuron cannot fire is termed the
A) absolutely (absolute) refractory period.
B) relatively (relative) refractory period.
C) hypostyle (ascending) refractory period.
D) adductory (closing) refractory period.

Accepted Answer

The absolute refractory period is the time immediately following an action potential during which a neuron is unable to fire another action potential, regardless of the strength of the stimulus.

Question 19

The period following depolarization of a neuron during which a neuron can fire, but requires a higher level of stimulation than required for the initial depolarization, is the
A) primary refractory period.
B) secondary refractory period.
C) absolutely (absolute) refractory period.
D) relatively (relative) refractory period.

Accepted Answer

The relative refractory period is the phase following depolarization when a neuron can fire again, but it requires a stronger stimulus than the initial depolarization.

Question 20

Inhibition causes
A) depolarization.
B) hyperpolarization.
C) repolarization.
D) none of the above.

Accepted Answer

Inhibition typically causes hyperpolarization, making the inside of a neuron more negative and less likely to fire an action potential.

Quiz 12: Neurophysiology

The basic function of a neuron is to

Neurotransmitter substance

An action potential is

EPSP refers to

The molecular "fuel" for active transport is

Myelinated fibers conduct the wave of depolarization more rapidly than demyelinated fibers

In biological systems, voltage is the product of

Voltage-sensitive proteins

Excitation causes

Electroencephalographic (EEG) recordings are actually records of

IPSP refers to

Communication between two neurons occurs at the

A neuron can fire approximately once every

Active cellular transport

Because an action potential always results in the same neural response,

An action potential causes

Adenosine triphosphate is a direct product of

The period following depolarization when a neuron cannot fire is termed the

The period following depolarization of a neuron during which a neuron can fire, but requires a higher level of stimulation than required for the initial depolarization, is the

Inhibition causes