Question 1

The blood-brain barrier protects the brain

Accepted Answer

A)  mostly during fetal development. 
B)  from fat-soluble substances. 
C)  by maintaining a brain blood supply that is separate from the circulation to the rest of the body. 
D)  through the action of astrocytes that reduce the permeability of small blood vessels. 
E)  and spinal cord and peripheral nervous system. 
A)  mostly during fetal development. 
B)  from fat-soluble substances. 
C)  by maintaining a brain blood supply that is separate from the circulation to the rest of the body. 
D)  through the action of astrocytes that reduce the permeability of small blood vessels. 
E)  and spinal cord and peripheral nervous system.

Question 2

Toxins such as those from bacteria of the genus Clostridium can cause diseases such as botulism by destroying the proteins that anchor vesicles to the presynaptic membrane.How might this affect activity in the neuromuscular junction?

Accepted Answer

A)  Postsynaptic cells would receive too much neurotransmitter, as reuptake by the presynaptic membrane would be impaired. 
B)  Voltage-gated Ca2+ channels would be unable to open in response to an action potential. 
C)  Neurotransmitter would not be released into the synaptic cleft. 
D)  Graded potentials would cause fusion of the vesicles with the cell membrane. 
E)  Entry of the neurotransmitter into the postsynaptic cell by endocytosis would be impaired. 
A)  Postsynaptic cells would receive too much neurotransmitter, as reuptake by the presynaptic membrane would be impaired. 
B)  Voltage-gated Ca2+ channels would be unable to open in response to an action potential. 
C)  Neurotransmitter would not be released into the synaptic cleft. 
D)  Graded potentials would cause fusion of the vesicles with the cell membrane. 
E)  Entry of the neurotransmitter into the postsynaptic cell by endocytosis would be impaired.

Question 3

Which statement about microglia is false?

Accepted Answer

A)  They are phagocytic cells. 
B)  They exist outside of the blood-brain barrier. 
C)  They are motile. 
D)  They provide immune defense responses. 
E)  They arise from blood-forming stem cells. 
A)  They are phagocytic cells. 
B)  They exist outside of the blood-brain barrier. 
C)  They are motile. 
D)  They provide immune defense responses. 
E)  They arise from blood-forming stem cells.

Question 4

Which of the following is not a type of glial cell?

Accepted Answer

A)  Oligodendrocyte 
B)  Bipolar cell 
C)  Schwann cell 
D)  Astrocyte 
E)  Microglia 
A)  Oligodendrocyte 
B)  Bipolar cell 
C)  Schwann cell 
D)  Astrocyte 
E)  Microglia

Question 5

Chemical synapses differ from electrical synapses in that they

Accepted Answer

A)  possess a greater variety of postsynaptic responses. 
B)  are faster. 
C)  contain numerous gap junctions. 
D)  have bidirectional transmission. 
E)  excel at synchronizing the activity of cells. 
A)  possess a greater variety of postsynaptic responses. 
B)  are faster. 
C)  contain numerous gap junctions. 
D)  have bidirectional transmission. 
E)  excel at synchronizing the activity of cells.

Question 6

Refer to the figure showing a cell membrane.   The figure illustrates the activity of a(n)

Accepted Answer

A)  channel through which ions are diffusing. 
B)  sodium‒potassium pump. 
C)  leak channel. 
D)  ion channel. 
E)  concentration gradient. 
A)  channel through which ions are diffusing. 
B)  sodium‒potassium pump. 
C)  leak channel. 
D)  ion channel. 
E)  concentration gradient.

Question 7

Refer to the figure showing the conduction of an action potential traveling from left to right in a myelinated axon.Note the action potential at node 2.   Which statement about this axon is false?

Accepted Answer

A)  Area 1 is a node of Ranvier. 
B)  An action potential will be triggered at node 3 as a result of the action potential occurring at node 2. 
C)  Action potentials can jump rapidly from node 1 to node 2. 
D)  An action potential traveling from left to right will leave node 1 refractory because its Na+ channels are still open. 
E)  Node 1 participates in saltatory conduction. 
A)  Area 1 is a node of Ranvier. 
B)  An action potential will be triggered at node 3 as a result of the action potential occurring at node 2. 
C)  Action potentials can jump rapidly from node 1 to node 2. 
D)  An action potential traveling from left to right will leave node 1 refractory because its Na+ channels are still open. 
E)  Node 1 participates in saltatory conduction.

Question 8

A drug that mimics or increases the effect of a neurotransmitter is called a(n) _______.

Accepted Answer

The answer of A drug that mimics or increases the...

Question 9

Which of the following would result from the inhibition of acetylcholinesterase?

Accepted Answer

A)  Release of neurotransmitter from the presynaptic membrane would be inhibited. 
B)  Synthesis of neurotransmitter in cells would be inhibited. 
C)  Breakdown of neurotransmitter in the synapse would be inhibited. 
D)  Stimulation of the postsynaptic membrane would be inhibited. 
E)  Cholinergic receptors would be inhibited. 
A)  Release of neurotransmitter from the presynaptic membrane would be inhibited. 
B)  Synthesis of neurotransmitter in cells would be inhibited. 
C)  Breakdown of neurotransmitter in the synapse would be inhibited. 
D)  Stimulation of the postsynaptic membrane would be inhibited. 
E)  Cholinergic receptors would be inhibited.

Question 10

In vertebrate nervous systems, most synapses between neurons are _______ whereas those between astrocytes are electrical.

Accepted Answer

The answer of In vertebrate nervous systems, most synapses between...

Question 11

Refer to the figure showing the knee-jerk reflex.   What would be the immediate result of severing the neuron shown at point 1?

Accepted Answer

Information from str

Question 12

A chemical synapse differs from an electrical synapse in that a chemical synapse

Accepted Answer

A)  allows for faster transmission of a signal. 
B)  allows for many more synaptic inputs per cell. 
C)  does not allow for temporal summation of synaptic inputs. 
D)  requires a larger area of cell‒cell contact. 
E)  cannot be inhibitory. 
A)  allows for faster transmission of a signal. 
B)  allows for many more synaptic inputs per cell. 
C)  does not allow for temporal summation of synaptic inputs. 
D)  requires a larger area of cell‒cell contact. 
E)  cannot be inhibitory.

Question 13

Certain poisons disable the sodium-potassium pump, which would cause sodium ions to increase and potassium ions to _______ inside cells.

Accepted Answer

The answer of Certain poisons disable the sodium-potassium pump, which...

Question 14

Neuromuscular junctions are synapses between _______ and _______ muscle cells.

Accepted Answer

A)  sensory neurons; skeletal 
B)  interneurons; skeletal 
C)  motor neurons; skeletal 
D)  sensory neurons; smooth 
E)  motor neurons; smooth 
A)  sensory neurons; skeletal 
B)  interneurons; skeletal 
C)  motor neurons; skeletal 
D)  sensory neurons; smooth 
E)  motor neurons; smooth

Question 15

Because of the voltage difference across the membrane of a neuron and the different ion concentrations on either side of the membrane, ions would cross the membrane if they could.What is the importance, therefore, of a neuron maintaining a membrane potential?

Accepted Answer

A)  It maintains an electrical balance in the cell. 
B)  Cellular activity requires more Na+ than K+. 
C)  If the ions were in equilibrium, the cell would shrink by losing water through osmosis. 
D)  It prevents the electrical and chemical gradients from reaching equilibrium, a process that would require a great deal of energy. 
E)  It allows a cell to respond to a stimulus that changes its permeability to ions. 
A)  It maintains an electrical balance in the cell. 
B)  Cellular activity requires more Na+ than K+. 
C)  If the ions were in equilibrium, the cell would shrink by losing water through osmosis. 
D)  It prevents the electrical and chemical gradients from reaching equilibrium, a process that would require a great deal of energy. 
E)  It allows a cell to respond to a stimulus that changes its permeability to ions.

Question 16

Refer to the figure showing a neuromuscular junction.   At which of the numbered positions would botulinum toxin have its effect, and what would be the result?

Accepted Answer

Botulinum toxin disrupts proteins that a

Question 17

Two electrodes, one on either side of the cell membrane of a resting neuron, show a difference of about ‒65 mV.If the value changes quickly to about +50 mV and then rapidly returns to ‒65 mV, the most likely explanation is that

Accepted Answer

A)  the cell membrane briefly became hyperpolarized. 
B)  a graded potential passed by the electrodes. 
C)  an action potential was triggered by changes in voltage-gated Na+ and K+ channels. 
D)  voltage-gated Na+ channels closed, causing a spike of depolarization, and then opened again. 
E)  leak K+ channels opened and then closed. 
A)  the cell membrane briefly became hyperpolarized. 
B)  a graded potential passed by the electrodes. 
C)  an action potential was triggered by changes in voltage-gated Na+ and K+ channels. 
D)  voltage-gated Na+ channels closed, causing a spike of depolarization, and then opened again. 
E)  leak K+ channels opened and then closed.

Question 18

Refer to the figure showing two types of neurons.   Compared with neuron B, neuron A would be more likely to

Accepted Answer

A)  communicate information over a short distance. 
B)  collect information from more cells. 
C)  process information from fewer cells. 
D)  depolarize after receiving an action potential. 
E)  process information more quickly from a single synapse. 
A)  communicate information over a short distance. 
B)  collect information from more cells. 
C)  process information from fewer cells. 
D)  depolarize after receiving an action potential. 
E)  process information more quickly from a single synapse.

Question 19

Failure of the blood-brain barrier has been implicated in triggering seizures.Which cells might be involved in failure of the blood-brain barrier?

Accepted Answer

A)  Neuroblasts 
B)  Oligodendrocytes 
C)  Microglia 
D)  Astrocytes 
E)  Schwann cells 
A)  Neuroblasts 
B)  Oligodendrocytes 
C)  Microglia 
D)  Astrocytes 
E)  Schwann cells

Question 20

If you knew the intracellular and extracellular concentrations of several ions in a liquid medium bathing cells, what else would you need to know to use the Goldman equation?

Accepted Answer

A)  The total number of cells 
B)  The membrane permeability for each ion 
C)  The leak current (due to leak channels) for K+ 
D)  The resting membrane potential 
E)  The charge of each ion 
A)  The total number of cells 
B)  The membrane permeability for each ion 
C)  The leak current (due to leak channels) for K+ 
D)  The resting membrane potential 
E)  The charge of each ion

Exam 44: Neurons, Glia, and Nervous Systems

The blood-brain barrier protects the brain

Toxins such as those from bacteria of the genus Clostridium can cause diseases such as botulism by destroying the proteins that anchor vesicles to the presynaptic membrane.How might this affect activity in the neuromuscular junction?

Which statement about microglia is false?

Which of the following is not a type of glial cell?

Chemical synapses differ from electrical synapses in that they

Refer to the figure showing a cell membrane. The figure illustrates the activity of a(n)

Refer to the figure showing the conduction of an action potential traveling from left to right in a myelinated axon.Note the action potential at node 2. Which statement about this axon is false?

A drug that mimics or increases the effect of a neurotransmitter is called a(n) _______.

Which of the following would result from the inhibition of acetylcholinesterase?

In vertebrate nervous systems, most synapses between neurons are _______ whereas those between astrocytes are electrical.

Refer to the figure showing the knee-jerk reflex. What would be the immediate result of severing the neuron shown at point 1?

A chemical synapse differs from an electrical synapse in that a chemical synapse

Certain poisons disable the sodium-potassium pump, which would cause sodium ions to increase and potassium ions to _______ inside cells.

Neuromuscular junctions are synapses between _______ and _______ muscle cells.

Because of the voltage difference across the membrane of a neuron and the different ion concentrations on either side of the membrane, ions would cross the membrane if they could.What is the importance, therefore, of a neuron maintaining a membrane potential?

Refer to the figure showing a neuromuscular junction. At which of the numbered positions would botulinum toxin have its effect, and what would be the result?

Two electrodes, one on either side of the cell membrane of a resting neuron, show a difference of about ‒65 mV.If the value changes quickly to about +50 mV and then rapidly returns to ‒65 mV, the most likely explanation is that

Refer to the figure showing two types of neurons. Compared with neuron B, neuron A would be more likely to

Failure of the blood-brain barrier has been implicated in triggering seizures.Which cells might be involved in failure of the blood-brain barrier?

If you knew the intracellular and extracellular concentrations of several ions in a liquid medium bathing cells, what else would you need to know to use the Goldman equation?

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Neuromuscular junctions are synapses between _ and _ muscle cells.