Question 1

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?
A) Specific sodium gates will open.
B) Sodium gates will open first, then close as potassium gates open.
C) A single type of channel will open, permitting simultaneous flow of sodium and potassium.
D) Specific potassium gates will open.

Accepted Answer

An EPSP is generated when a single type of channel opens, allowing both sodium ions to flow into the cell and potassium ions to flow out, leading to a net depolarization.

Question 2

An inhibitory postsynaptic potential (IPSP) is associated with .
A) hyperpolarization
B) opening of voltage- regulated channels
C) a change in sodium ion permeability
D) lowering the threshold for an action potential to occur

Accepted Answer

An IPSP is associated with hyperpolarization, which makes the inside of the cell more negative and moves the membrane potential further from the threshold needed to trigger an action potential.

Question 3

Collections of nerve cell bodies outside the central nervous system are called .
A) ganglia
B) tracts
C) nuclei
D) nerves

Accepted Answer

Ganglia are collections of nerve cell bodies located outside the central nervous system.

Question 4

Which of the following describes the nervous system integrative function?
A) senses changes in the environment
B) responds to stimuli by gland secretion or muscle contraction
C) analyzes sensory information, stores information, makes decisions

Accepted Answer

The integrative function of the nervous system involves analyzing sensory information, storing it, and making decisions based on that information.

Question 5

Which of the following is not a function of astrocytes?
A) guide the migration of young neurons, synapse formation, and helping to determine capillary permeability
B) support and brace neurons
C) control the chemical environment around neurons
D) anchor neurons to blood vessels
E) provide the defense for the CNS

Accepted Answer

Astrocytes do not provide defense for the CNS; this function is primarily carried out by microglia, which act as the main immune defense in the central nervous system.

Question 6

Which of the following is not characteristic of neurons?
A) They have extreme longevity.
B) They conduct impulses.
C) They have an exceptionally high metabolic rate.
D) They are mitotic.

Accepted Answer

Neurons are generally considered to be amitotic, meaning they do not undergo mitosis and cannot divide to produce new neurons.

Question 7

In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is .
A) negatively charged and contains less sodium
B) positively charged and contains more sodium
C) negatively charged and contains more sodium
D) positively charged and contains less sodium

Accepted Answer

The interior of a resting neuron's cell membrane is negatively charged compared to the outside, and it contains less sodium due to the action of the sodium-potassium pump and differential permeability to ions.

Question 8

A second nerve impulse cannot be generated until .
A) the membrane potential has been reestablished
B) all sodium gates are closed
C) proteins have been resynthesized
D) the Na ions have been pumped back into the cell

Accepted Answer

A second nerve impulse cannot be generated until the membrane potential has been reestablished, which occurs during the refractory period after the initial impulse.

Question 9

What does the central nervous system use to determine the strength of a stimulus?
A) type of stimulus receptor
B) origin of the stimulus
C) frequency of action potentials
D) size of action potentials

Accepted Answer

The central nervous system determines the strength of a stimulus by the frequency of action potentials. A stronger stimulus will generate action potentials at a higher frequency.

Question 10

What is the role of acetylcholinesterase?
A) stimulate the production of acetylcholine
B) destroy ACh a brief period after its release by the axon endings
C) act as a transmitting agent
D) amplify or enhance the effect of ACh

Accepted Answer

Acetylcholinesterase is an enzyme that breaks down acetylcholine (ACh) into choline and acetate. This prevents ACh from building up in the synaptic cleft and causing overstimulation of the postsynaptic cell.

Question 11

When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) .
A) action potential
B) excitatory potential
C) generator potential
D) postsynaptic potential

Accepted Answer

A generator potential is the graded potential that occurs in a sensory neuron when it is excited by some form of energy.

Question 12

Which of the following is not a function of the autonomic nervous system?
A) innervation of smooth muscle of the digestive tract
B) innervation of glands
C) innervation of cardiac muscle
D) innervation of skeletal muscle

Accepted Answer

The autonomic nervous system controls involuntary functions and innervates smooth muscle, cardiac muscle, and glands, but not skeletal muscle, which is controlled by the somatic nervous system.

Question 13

Which of the following neurotransmitters inhibits pain and is mimicked by morphine, heroin, and methadone?
A) acetylcholine
B) nitric oxide
C) serotonin
D) endorphin

Accepted Answer

Endorphins are neurotransmitters that inhibit pain and are mimicked by opioids like morphine, heroin, and methadone.

Question 14

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?
A) cholinesterase
B) acetylcholine
C) norepinephrine
D) gamma aminobutyric acid

Accepted Answer

Acetylcholine is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle.

Question 15

The substance released at axon terminals to propagate a nervous impulse is called a(n) .
A) biogenic amine
B) ion
C) cholinesterase
D) neurotransmitter

Accepted Answer

Neurotransmitters are chemicals released at axon terminals to transmit signals across a synapse to another neuron or target cell.

Question 16

Which of the following is not true of graded potentials?
A) They increase amplitude as they move away from the stimulus point.
B) They can be called postsynaptic potentials.
C) They are short- lived.
D) They can form on receptor endings.

Accepted Answer

Graded potentials decrease in amplitude as they move away from the stimulus point due to the leakage of charge across the membrane.

Question 17

Which of the following is true about the movement of ions across excitable living membranes?
A) Ions always move actively across membranes through leakage channels.
B) Ions always move from an area of higher concentration to an area of lower concentration
C) Sodium gates in the membrane can open in response to electrical potential changes.
D) Ions always move passively across membranes.

Accepted Answer

Sodium gates in the membrane can open in response to changes in electrical potential, allowing ions to move across the membrane during processes like action potentials.

Question 18

If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon _ .
A) muscle contraction would occur
B) the impulse would move to the axon terminal only, and the muscle contraction would occur
C) the impulse would spread bidirectionally
D) the impulse would move to the axon terminal only

Accepted Answer

When a motor neuron is stimulated at the midpoint of the axon, the action potential can propagate in both directions from the point of stimulation, moving towards both the axon terminal and the cell body.

Question 19

A neuron that has as its primary function the job of connecting other neurons is called a(n)
)
A) afferent neuron
B) glial cell
C) association neuron
D) efferent neuron

Accepted Answer

Association neurons, also known as interneurons, primarily function to connect other neurons within the central nervous system.

Question 20

Which of the following is false or incorrect?
A) An excitatory postsynaptic potential occurs if the excitatory effect is greater than the inhibitory effect but less than threshold.
B) An inhibitory postsynaptic potential occurs if the inhibitory effect is greater than the excitatory, causing hyperpolarization of the membrane.
C) A nerve impulse occurs if the excitatory and inhibitory effects are equal.

Accepted Answer

A nerve impulse occurs only if the excitatory effect is strong enough to surpass the threshold and create an action potential. If the effects are equal, there is no net change in the membrane potential and no action potential is generated.

Quiz 11: Fundamentals of the Nervous System and Nervous Tissue

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?

An inhibitory postsynaptic potential (IPSP) is associated with .

Collections of nerve cell bodies outside the central nervous system are called .

Which of the following describes the nervous system integrative function?

Which of the following is not a function of astrocytes?

Which of the following is not characteristic of neurons?

In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is .

A second nerve impulse cannot be generated until .

What does the central nervous system use to determine the strength of a stimulus?

What is the role of acetylcholinesterase?

When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) .

Which of the following is not a function of the autonomic nervous system?

Which of the following neurotransmitters inhibits pain and is mimicked by morphine, heroin, and methadone?

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?

The substance released at axon terminals to propagate a nervous impulse is called a(n) .

Which of the following is not true of graded potentials?

Which of the following is true about the movement of ions across excitable living membranes?

If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon _ .

A neuron that has as its primary function the job of connecting other neurons is called a(n) )

Which of the following is false or incorrect?