Deck 41: Neural Signaling

Question 1

Which of the following events concerning a response to a stimulus comes first?

A) transmission
B) reception
C) action by effectors
D) involvement of the brain and spinal cord
E) integration

Answer 1

B

Question 2

The transmission of your voice from your cell phone to the cell phone tower most closely resembles:

A) afferent neurons transmitting information to the central nervous system.
B) glial cells providing a support network for the nervous system.
C) interneurons connecting motor and sensory neurons.
D) efferent neurons transmitting information from the central nervous system to an effector.
E) the brain sending an electrical signal down the spinal cord to your leg.

Answer 2

A

Question 3

Which neurons integrate information coming into and out of the central nervous system?

A) afferent neurons
B) motor neurons
C) interneurons
D) efferent neurons
E) sensory neurons

Answer 3

C

Question 4

Figure 41-1
Use the figure to answer the corresponding question(s).
What would happen if all of the structures corresponding to the one labeled 6 in Figure 41-1 were removed from the neuron?

A) Impulse transmission would be faster.
B) Impulse transmission would be slower.
C) Impulse transmission would cease.
D) Continuous conduction would occur.
E) There would be no effect on transmission.

Question 5

Which statement about the structure of neurons is true?

A) Dendrites carry impulses away from the cell body.
B) Axons may form branches known as collaterals.
C) Nerve impulses travel down the axon toward the cell body.
D) Dendrites are often myelinated for faster conduction.
E) Synapses occur between the cell body and its axon.

Question 6

Which of the following provides insulation for the neuron?

A) synapse
B) axon
C) dendrite
D) Schwann cell
E) microglial cell

Question 7

Afferent neurons:

A) transmit information to the central nervous system.
B) provide support for the neurons.
C) connect motor and sensory neurons.
D) transmit information from the central nervous system to effectors.
E) are part of the central nervous system.

Question 8

An example of an effector is a(n):

A) sense organ
B) efferent neuron
C) afferent neuron
D) muscle
E) interneuron

Question 9

Figure 41-1
Use the figure to answer the corresponding question(s).
Gaps in the myelin sheath are referred to as:

A) synapses.
B) neuroglia.
C) microglia.
D) Schwann cells.
E) Nodes of Ranvier.

Question 10

In a resting neuron:

A) the concentration of potassium ions is about 10 times greater inside the cell than in the extracellular fluid.
B) excitatory postsynaptic potentials hyperpolarize the membrane.
C) voltage-activated sodium channels are pumping sodium inside the cell against its concentration gradient.
D) the membrane is more permeable to sodium than potassium ions.
E) inhibitory postsynaptic potentials depolarize the membrane.

Question 11

The myelin sheath:

A) is a protein covering around dendrites.
B) is responsible for integrating information.
C) is a fatty covering only around axons.
D) stores neurotransmitters in the axon.
E) is a fatty covering only around cell bodies.

Question 12

Figure 41-1
Use the figure to answer the corresponding question(s).
Each structure labeled 4 in Figure 41-1 is:

A) a node of Ranvier.
B) a cell body.
C) a dendrite.
D) a synaptic terminal.
E) an axon.

Question 13

In multiple sclerosis, a victim:

A) loses coordination due to the replacement of myelin with scar tissue.
B) accumulates neurofibrillary tangles in the brain resulting in dementia.
C) suffers tremors due to overly rapid and spontaneous firing of neural impulses.
D) is unable to transmit neural impulses because poisons interfere with the action of the ion pumps.
E) suffers depression due to abnormal secretion of neurotransmitters.

Question 14

If you were a researcher interested in trying to find a cure for multiple sclerosis, in which area would you focus your research?

A) understanding how myelin synthesis is regulated
B) understanding why neurofibrillary tangles occur in the brain
C) understanding how neural impulses are transmitted to other nerves
D) understanding the action of the ion pumps
E) understanding the regulation of neurotransmitter secretion and recycling

Question 15

Figure 41-1
Use the figure to answer the corresponding question(s).
The function of the structure labeled 6 in Figure 41-1 is:

A) insulation.
B) neurotransmitter release.
C) binding neurotransmitters.
D) conduction of an electrical signal.
E) acting as a ligand-gated channel.

Question 16

Which of the following statements concerning glial cells is true?

A) Astrocytes are phagocytic cells that remove debris in the central nervous system.
B) Schwann cells form sheaths around neurons within the central nervous system.
C) Oligodendrocytes regulate the concentration of neurotransmitters in neurons.
D) Microglia are involved in the neurological disease multiple sclerosis.
E) Ependymal cells help produce and circulate cerebrospinal fluid.

Question 17

Maintenance of the resting membrane potential is accomplished by:

A) saltatory conduction down the axon.
B) an excess of calcium ions outside the myelin sheath.
C) an accumulation of more positive ions outside the neuron than inside.
D) the voltage-gated potassium ion channels.
E) the storage of acetylcholine in the nerve terminal.

Question 18

A nerve consists of:

A) a grouping of dendrites.
B) a mass of cell bodies.
C) a network of neurons.
D) a bundle of axons.
E) glial cells.

Question 19

Which of the following would not be considered part of the peripheral nervous system?

A) the eyes
B) the spinal cord
C) afferent neurons
D) the ears
E) efferent neurons

Question 20

The initial response to a stimulus involves which process?

A) perception
B) integration
C) interpretation
D) reception
E) sensation

Question 21

Saltatory conduction:

A) does not involve voltage-activated potassium ion channels.
B) can occur in both myelinated and unmyelinated neurons.
C) is slightly slower than continuous conduction.
D) is more energy efficient than continuous conduction.
E) allows nerve impulses to jump from Schwann cell to Schwann cell.

Question 22

A nerve impulse moves along a neuron as:

A) sodium moves into the cell and potassium moves out of the cell.
B) sodium binds to potassium.
C) sodium and potassium are pulled apart.
D) acetylcholine moves along the nerve fiber.
E) calcium exits the dendrites.

Question 23

Figure 41-2
Use the figure to answer the corresponding question(s).
The ion flow in part 1 of Figure 41-2:

A) represents the equilibrium potential.
B) represents the resting state.
C) will increase the rate of repolarization.
D) will reestablish the electronegative resting potential.
E) represents the initial response of a neuron to an action potential.

Question 24

Figure 41-2
Use the figure to answer the corresponding question(s).

-Based on part 2 of Figure 41-2, the ions involved in __________ are __________.

A) depolarization; Cl^-
B) repolarization; K⁺
C) depolarization; Na⁺
D) repolarization; Cl ^-
E) hyperpolarization; Na⁺

Question 25

Figure 41-2
Use the figure to answer the corresponding question(s).
Refer to Figure 41-2.Which of the following would have an effect on the structure in part 1?

A) potassium concentration
B) chloride concentration
C) neurotoxin
D) tetrodotoxin
E) provocain

Question 26

A steady state, or equilibrium potential, in a neuron is reached when:

A) the outflow of sodium equals the inflow of potassium.
B) the inflow of sodium equals the inflow of potassium.
C) the outflow of potassium equals the inflow of potassium.
D) the outflow of sodium equals the inflow of sodium.
E) the outflow of calcium equals the inflow of sodium.

Question 27

Figure 41-3
Use the figure to answer the corresponding question(s).
Novocain would work at which point in Figure 41-3?

A) 1
B) 2
C) 3
D) E
E) 4

Question 28

Which statement about chemical or electrical synapses is true?

A) Electrical synapses require a neurotransmitter.
B) In electrical synapses, presynaptic and postsynaptic neurons are separated by synaptic clefts.
C) Electrical synapses store excess ions in synaptic vesicles.
D) In chemical synapses, presynaptic and postsynaptic neurons are connected by a protein channel.
E) Electrical synapses involve the transfer of ions from presynaptic to postsynaptic neurons.

Question 29

The resting potential of a neuron is due to all of the following except:

A) potassium being at a higher concentration inside the cell than out.
B) sodium being at a higher concentration outside the cell than in.
C) cells being more permeable to potassium than to sodium.
D) the cytosol containing large molecules having a net negative charge.
E) the sodium/potassium pump transporting 3 Na⁺ into the cell for every 2 K⁺ out.

Question 30

During a relative refractory period:

A) an axon can transmit impulses comparable to a resting neuron.
B) an axon cannot transmit an action potential at all.
C) an axon can transmit impulses, but the threshold level is higher.
D) all voltage-activated sodium channels are inactivated.
E) neurons can only transmit several impulses per second.

Question 31

Any type of stimulus can alter resting potential by increasing the permeability of the membrane to:

A) potassium.
B) sodium.
C) calcium.
D) neurotransmitters.
E) enkephalins.

Question 32

Figure 41-3
Use the figure to answer the corresponding question(s).
In Figure 41-3, point A is:

A) the resting state.
B) indicative of repolarization.
C) the threshold level.
D) the equilibrium potential.
E) indicative of hyperpolarization.

Question 33

Figure 41-3
Use the figure to answer the corresponding question(s).
Step 2 in Figure 41-3 is accomplished by:

A) an influx of Ca²⁺.
B) an influx of Na²⁺.
C) an influx of K⁺.
D) an efflux of Na²⁺.
E) an efflux of K⁺.

Question 34

The role of the Na/K pump in action potential is to:

A) allow movement of sodium into the cell.
B) allow movement of potassium out of the cell.
C) allow movement of potassium into and sodium out of the cell.
D) allow movement of both ions into the cell.
E) allow movement of both ions out of the cell.

Question 35

Figure 41-3
Use the figure to answer the corresponding question(s).
Since all action potentials are identical, the intensity of a sensation depends on:

A) whether a myelinated or unmyelinated neuron has been stimulated.
B) the duration of the stimulation.
C) whether the neuron stimulated is a pre- or postsynaptic neuron.
D) the total number of neurons stimulated and the frequency of their discharge.
E) the presence of an EPSP or IPSP, which allows for a graded response.

Question 36

Figure 41-2
Use the figure to answer the corresponding question(s).
When the membrane potential of a neuron reaches the threshold level:

A) voltage-gated sodium channels open, and sodium diffuses out of the cell.
B) voltage-gated potassium channels open for a very brief period.
C) voltage-gated sodium channels close, so sodium cannot diffuse out of the cell.
D) the sodium channel protein changes its shape to open the gates of the channel.
E) the membrane potential is more negative than when at rest.

Question 37

Figure 41-2
Use the figure to answer the corresponding question(s).
When the dentist gives you a shot of Novocain, why to you not feel any pain when s/he drills into your tooth?

A) The neuron remains in the depolarized state.
B) A transmembrane potential does not form.
C) The drug decreases the external Na⁺ concentration.
D) Voltage-activated K⁺ channels are blocked.
E) Nerve transmission is blocked.

Question 38

Which of the following statements about the speed of impulse conduction in a neuron is true?

A) Longer axons can transmit impulses faster than shorter ones.
B) Unmyelinated axons transmit impulses faster than myelinated ones.
C) Shorter axons can transmit impulses faster than longer ones.
D) Nerve impulses travel faster than the speed of light.
E) Unmyelinated axons with larger diameters transmit impulses faster than ones with small diameters.

Question 39

Figure 41-3
Use the figure to answer the corresponding question(s).
The all-or-none reaction means that:

A) if a stimulus is strong enough, all axons in a nerve bundle will fire simultaneously.
B) a neuron will only produce an action potential if it has been depolarized to its threshold level.
C) all neurons discharge impulses at the same frequency.
D) a neuron can create an action potential of varying intensities.
E) either all or none of the neurons will fire impulses when stimulated.

Question 40

Which of the following statements about a resting transmembrane potential is true?

A) If the sodium-potassium pump were blocked, the transmembrane potential would become greater.
B) If the resting neuron were suddenly made permeable to positive ions, a transmembrane potential would not form.
C) If the resting neuron had no voltage-activated K⁺ channels, K⁺ concentrations in cytoplasm would increase.
D) If the voltage-activated Na⁺ channels are blocked, Na⁺ will not enter the cytoplasm of the neuron.
E) If the cytosol developed a negative charge, the resting potential would disappear..

Question 41

Make a sketch that shows how the neuron develops and maintains a resting potential.BONUS: What is the approximate value of this resting potential in a typical neuron?

Question 42

What would happen if a neuron with a resting membrane potential of -100 mV and a threshold level of -70 mV received three IPSPs of -5 mV and four EPSPs of -10 mV in close succession?

Question 43

The amyloid plaques associated with Alzheimer's disease:

A) are associated with neurons lacking microglia.
B) are formed from the shortest known form of beta-amyloid molecules.
C) have been linked to mutations in genes that produced abnormal beta-amyloid.
D) result in disruption of sodium regulation.
E) are responsible for 90% of the diagnosed cases of this disease.

Question 44

Neurofibrillary tangles occur:

A) in the neuron cytoplasm of patients with Alzheimer's disease.
B) in the axon of patients with multiple sclerosis.
C) in the glial cells of patients with myasthenia gravis.
D) in the dendrites of patients with peripheral neuropathy.
E) in the cell bodies of patients with depression.

Question 45

Diagram a typical neuron, label its parts, and list the function of each labeled structure.

Question 46

Spatial summation occurs when

A) several neurons in an area fire at one time.
B) neurons fire repeatedly until a stimulus is sent.
C) they are too weak to cause an action potential.
D) the post-synaptic neuron is stimulated in one location.
E) the pre-synaptic neuron fires into many post-synaptic neurons.

Question 47

The reuptake of serotonin by neurons in the brain can be inhibited by:

A) astrocytes.
B) antidepressant medications.
C) Valium.
D) enkephalin.
E) nitrous oxide.

Question 48

Ligand-gated ion channels bind __________ to allow passage of ions.

A) enzymes
B) ions
C) neurotransmitters
D) steroid hormones
E) phospholipids

Question 49

In divergence, one neuron:

A) is controlled by several neurons.
B) is controlled by several neurotransmitter substances.
C) contains several different types of ion channels.
D) controls several other neurons.
E) contains several different types of receptors.

Question 50

The neuropeptide neurotransmitters are involved in:

A) pain regulation.
B) stimulation of skeletal muscle.
C) inhibition of acetylcholine receptors.
D) mood regulation.
E) release of hormones.

Question 51

An inhibitory post-synaptic impulse (IPSP):

A) is represented by a movement of the neuron to a more positive voltage.
B) moves the neuron further away from firing.
C) involves the action of acetylcholine.
D) occurs when Na⁺ ion channels open.
E) occurs when K⁺ ion channels close.

Question 52

Which of the following characteristics is not true of excitatory postsynaptic potentials and inhibitory postsynaptic potentials?

A) They may both be summed spatially or temporally.
B) Both EPSPs and IPSPs are graded potentials.
C) IPSPs cancel the effects of some of the EPSPs.
D) Each EPSP or IPSP affects the membrane potential of the neuron.
E) They both represent an all-or-none response.

Question 53

Arrange the events of a second messenger system in the correct order. 1)
Protein kinase is activated
2)
G protein is activated
3)
Neurotransmitter binds to its receptor
4)
Protein closes potassium channel
5)
Cyclic AMP is produced
6)
Phosphorylation takes place

A) 1 $\rightarrow$ 2 $\rightarrow$ 5 $\rightarrow$ 6 $\rightarrow$ 4 $\rightarrow$ 3
B) 3 $\rightarrow$ 5 $\rightarrow$ 6 $\rightarrow$ 1 $\rightarrow$ 2 $\rightarrow$ 4
C) 5 $\rightarrow$ 2 $\rightarrow$ 6 $\rightarrow$ 1 $\rightarrow$ 3 $\rightarrow$ 4
D) 3 $\rightarrow$ 2 $\rightarrow$ 5 $\rightarrow$ 1 $\rightarrow$ 6 $\rightarrow$ 4
E) 5 $\rightarrow$ 2 $\rightarrow$ 6 $\rightarrow$ 1 $\rightarrow$ 4 $\rightarrow$ 3

Question 54

Compare and contrast the production and transmission of a graded potential with those of an action potential.

Question 55

Which class of neurotransmitters is linked to depression and schizophrenia?

A) opiates
B) catecholamines
C) endorphins
D) nitric oxides
E) adrenergic

Question 56

An excitatory postsynaptic potential (EPSP):

A) results in a partial depolarization of the neuron.
B) causes a neuron to fire.
C) prevents a neuron from firing.
D) results in a partial hyperpolarization of the neuron.
E) results in partial depolarization of presynaptic neurons, causing ions to pass through connecting channels.

Question 57

An example of a neurotransmitter that works by activation of G proteins is:

A) acetylcholine.
B) nitrous oxide.
C) endorphins.
D) GABA.
E) serotonin.

Question 58

Which of the following is not characteristic of neurotransmitters?

A) They are released in response to calcium ions.
B) They are chemical messengers that signal neurons, muscles, or glands.
C) They are stored within synaptic vesicles.
D) They are transported down axons to the synaptic terminals.
E) They move via diffusion across the synaptic cleft.

Question 59

Briefly explain the action of a neurotransmitter.Include information regarding the source, target, and mode of operation of a neurotransmitter.

Question 60

Repolarization of a postsynaptic cell can occur when:

A) there is a high enough concentration of neurotransmitters in the synaptic cleft.
B) neurotransmitters undergo exocytosis from the presynaptic cell.
C) enzymes degrade neurotransmitters in the synaptic cleft.
D) neurotransmitters are not removed from their receptors.
E) neurotransmitters undergo reuptake at the postsynaptic cell.

Question 61

Axons transmit neural impulses toward the cell body.
____________________

Question 62

Acetylcholine is a neurotransmitter released from motor neurons.
____________________

Question 63

In saltatory conduction, the membrane is depolarized only in the region of the myelin sheath.
____________________

Question 64

Star-shaped neuroglia are called astrocytes.
____________________

Question 65

The resting potential of a typical neuron is approximately +70 mV.
____________________

Question 66

The sodium-potassium pump transports two Na⁺ out of the cell for every two K⁺ transported in.
____________________

Question 67

MATCHING
Match the part of the neuron with its description.
a.axon
d.node of Ranvier
b.dendrite
e.synaptic vesicle
c.myelin sheath
a Schwann cell may form this

Question 68

Ependymal cells are a type of macrophage.
____________________

Question 69

Neurotransmitters move by active transport across the synaptic cleft.
____________________

Question 70

MATCHING
Match the part of the neuron with its description.
a.axon
d.node of Ranvier
b.dendrite
e.synaptic vesicle
c.myelin sheath
may be more than 1 meter long

Question 71

The arrival of an action potential at a synaptic terminal causes voltage-gated potassium channels to open.
____________________

Question 72

In convergence, a single neuron is controlled by signals from two or more presynaptic neurons.
____________________

Question 73

MATCHING
Match the part of the neuron with its description.
a.axon
d.node of Ranvier
b.dendrite
e.synaptic vesicle
c.myelin sheath
transports neural impulses away from the cell body

Question 74

In a neuron at rest, there is a higher concentration of sodium ions outside the cell than inside.
____________________

Question 75

MATCHING
Match the part of the neuron with its description.
a.axon
d.node of Ranvier
b.dendrite
e.synaptic vesicle
c.myelin sheath
an oligodendrocyte may form this

Question 76

MATCHING
Match the part of the neuron with its description.
a.axon
d.node of Ranvier
b.dendrite
e.synaptic vesicle
c.myelin sheath
neurotransmitters are stored here

Question 77

An EPSP is an example of a graded potential.
____________________

Question 78

During the absolute refractory period, the axon membrane cannot transmit another action potential.
____________________

Question 79

MATCHING
Match the part of the neuron with its description.
a.axon
d.node of Ranvier
b.dendrite
e.synaptic vesicle
c.myelin sheath
acetylcholine is stored here

Question 80

A strong stimulus will cause the neuron to generate a larger action potential than does a weaker stimulus.
____________________