Question 1

Briefly describe the all-or-none law of action potentials.

Accepted Answer

Once a neuron reaches the threshold of a

Question 2

Just after the peak of the action potential, what movement of ions restores the membrane to approximately the resting potential?

Accepted Answer

A)  Sodium ions enter the cell. 
B)  Potassium ions enter the cell. 
C)  Potassium ions leave the cell. 
D)  Sodium ions travel down the axon. 
A)  Sodium ions enter the cell. 
B)  Potassium ions enter the cell. 
C)  Potassium ions leave the cell. 
D)  Sodium ions travel down the axon.

Question 3

What tends to open the sodium gates across a neuron's membrane?

Accepted Answer

A)  hyperpolarization of the membrane 
B)  depolarization of the membrane 
C)  increase in the sodium concentration outside the neuron 
D)  passing the peak of the action potential and entering the refractory period 
A)  hyperpolarization of the membrane 
B)  depolarization of the membrane 
C)  increase in the sodium concentration outside the neuron 
D)  passing the peak of the action potential and entering the refractory period

Question 4

What causes potassium ions to leave the axon just after the peak of the action potential?

Accepted Answer

A)  a continuing concentration gradient and the opening of the potassium gates 
B)  an increase in the concentration gradient across the membrane 
C)  increased tendency of the sodium-potassium pump to pump potassium out 
D)  binding of potassium ions to proteins that leave at this time 
A)  a continuing concentration gradient and the opening of the potassium gates 
B)  an increase in the concentration gradient across the membrane 
C)  increased tendency of the sodium-potassium pump to pump potassium out 
D)  binding of potassium ions to proteins that leave at this time

Question 5

Voltage-activated channels are channels for which a change in the voltage across the membrane alters their:

Accepted Answer

A)  permeability. 
B)  length. 
C)  number. 
D)  threshold. 
A)  permeability. 
B)  length. 
C)  number. 
D)  threshold.

Question 6

At rest, the inside of a neuron's membrane is more negative than the outside.

Accepted Answer

A) True 
 B)False

Question 7

Which of the following is the correct order of transmission of information within a neuron?

Accepted Answer

A)  cell body, dendrite, axon 
B)  dendrite, axon, cell body 
C)  axon, cell body, dendrite 
D)  dendrite, cell body, axon 
A)  cell body, dendrite, axon 
B)  dendrite, axon, cell body 
C)  axon, cell body, dendrite 
D)  dendrite, cell body, axon

Question 8

The sodium-potassium pump pumps sodium ions ____ and potassium ions ____.

Accepted Answer

A)  into the cell; into the cell 
B)  into the cell; out of the cell 
C)  out of the cell; out of the cell 
D)  out of the cell; into the cell 
A)  into the cell; into the cell 
B)  into the cell; out of the cell 
C)  out of the cell; out of the cell 
D)  out of the cell; into the cell

Question 9

Which of the following is NOT true for sodium ions when the cell is at resting potential?

Accepted Answer

A)  Sodium ions remain outside the cell because the sodium- potassium pump drives them out. 
B)  Sodium gates are tightly closed. 
C)  Sodium tends to be driven into the neuron by the concentration gradient. 
D)  Sodium tends to be driven out of the neuron by the electrical gradient. 
A)  Sodium ions remain outside the cell because the sodium- potassium pump drives them out. 
B)  Sodium gates are tightly closed. 
C)  Sodium tends to be driven into the neuron by the concentration gradient. 
D)  Sodium tends to be driven out of the neuron by the electrical gradient.

Question 10

Prior to the work of Santiago Ramon y Cajal, what did many investigators believe?

Accepted Answer

A)  Nerves conducted impulses at the speed of light. 
B)  Transmission across a synapse was just as fast as transmission along an axon. 
C)  The tip of an axon physically merged with the next neuron. 
D)  All neurons were of similar size and shape. 
A)  Nerves conducted impulses at the speed of light. 
B)  Transmission across a synapse was just as fast as transmission along an axon. 
C)  The tip of an axon physically merged with the next neuron. 
D)  All neurons were of similar size and shape.

Question 11

Why does the brain need thiamine?

Accepted Answer

A)  to enable glucose to cross the blood-brain barrier 
B)  as a source of fuel in case there is not enough glucose 
C)  as a building block for making proteins 
D)  to enable it to metabolize glucose 
A)  to enable glucose to cross the blood-brain barrier 
B)  as a source of fuel in case there is not enough glucose 
C)  as a building block for making proteins 
D)  to enable it to metabolize glucose

Question 12

The general rule among neurons is that the wider the branching, the fewer connections with other neurons.

Accepted Answer

A) True 
 B)False

Question 13

Which of these is true of glial cells?

Accepted Answer

A)  They are larger than neurons 
B)  They transmit information over long distances. 
C)  They do not transmit information over long distances. 
D)  They are less numerous then neurons. 
A)  They are larger than neurons 
B)  They transmit information over long distances. 
C)  They do not transmit information over long distances. 
D)  They are less numerous then neurons.

Question 14

Which of the following is most likely to cross the cell membrane by simple diffusion?

Accepted Answer

A)  large proteins 
B)  small, charged ions 
C)  small, uncharged molecules 
D)  large, charged ions 
A)  large proteins 
B)  small, charged ions 
C)  small, uncharged molecules 
D)  large, charged ions

Question 15

Which of the following is TRUE of local neurons?

Accepted Answer

A)  They exchange information with distant neurons. 
B)  They abide by the all-or-none principle. 
C)  The change in membrane potential increases as it travels. 
D)  They have short dendrites and axons. 
A)  They exchange information with distant neurons. 
B)  They abide by the all-or-none principle. 
C)  The change in membrane potential increases as it travels. 
D)  They have short dendrites and axons.

Question 16

The difference in voltage in a resting neuron is called the resting potential.

Accepted Answer

A) True 
 B)False

Question 17

Which of the following events would increase the concentration gradient of sodium?

Accepted Answer

A)  decreased permeability to potassium ions 
B)  increased activity of the sodium potassium pump 
C)  increased membrane permeability to sodium ions 
D)  increased membrane permeability to chloride ions 
A)  decreased permeability to potassium ions 
B)  increased activity of the sodium potassium pump 
C)  increased membrane permeability to sodium ions 
D)  increased membrane permeability to chloride ions

Question 18

If a drug was given that temporarily inactivated the sodium-potassium pumps, action potentials would cease immediately.

Accepted Answer

A) True 
 B)False

Question 19

Of the following, the most important consideration in developing a drug that will act in the brain is:

Accepted Answer

A)  if the drug can be inexpensively manufactured. 
B)  if the drug will cross the blood-brain barrier. 
C)  how long the drug will act. 
D)  the number of people who will use the drug. 
A)  if the drug can be inexpensively manufactured. 
B)  if the drug will cross the blood-brain barrier. 
C)  how long the drug will act. 
D)  the number of people who will use the drug.

Question 20

According to the all-or-none law:

Accepted Answer

A)  all neurons produce an action potential at the same time or none at all. 
B)  all of the extracellular sodium enters the axon, or none at all. 
C)  once an axon reaches threshold, the amplitude and velocity of an action potential are nearly equal each time. 
D)  neurons are either active all the time or not at all. 
A)  all neurons produce an action potential at the same time or none at all. 
B)  all of the extracellular sodium enters the axon, or none at all. 
C)  once an axon reaches threshold, the amplitude and velocity of an action potential are nearly equal each time. 
D)  neurons are either active all the time or not at all.

Briefly describe the all-or-none law of action potentials.

Just after the peak of the action potential, what movement of ions restores the membrane to approximately the resting potential?

What tends to open the sodium gates across a neuron's membrane?

What causes potassium ions to leave the axon just after the peak of the action potential?

Voltage-activated channels are channels for which a change in the voltage across the membrane alters their:

At rest, the inside of a neuron's membrane is more negative than the outside.

Which of the following is the correct order of transmission of information within a neuron?

The sodium-potassium pump pumps sodium ions and potassium ions .

Which of the following is NOT true for sodium ions when the cell is at resting potential?

Prior to the work of Santiago Ramon y Cajal, what did many investigators believe?

Why does the brain need thiamine?

The general rule among neurons is that the wider the branching, the fewer connections with other neurons.

Which of these is true of glial cells?

Which of the following is most likely to cross the cell membrane by simple diffusion?

Which of the following is TRUE of local neurons?

The difference in voltage in a resting neuron is called the resting potential.

Which of the following events would increase the concentration gradient of sodium?

If a drug was given that temporarily inactivated the sodium-potassium pumps, action potentials would cease immediately.

Of the following, the most important consideration in developing a drug that will act in the brain is:

According to the all-or-none law:

The Major Issues

Synapses

Anatomy of the Nervous System

Development and Plasticity of the Brain

Vision

The Other Sensory Systems

Movement

Wakefulness and Sleep

Internal Regulation

Reproductive Behaviors

Emotional Behaviors

The Biology of Learning and Memory

Cognitive Functions

Mood Disorders and Schizophrenia

Filters

Exam 2: Nerve Cells and Nerve Impulses

Briefly describe the all-or-none law of action potentials.

Just after the peak of the action potential, what movement of ions restores the membrane to approximately the resting potential?

What tends to open the sodium gates across a neuron's membrane?

What causes potassium ions to leave the axon just after the peak of the action potential?

Voltage-activated channels are channels for which a change in the voltage across the membrane alters their:

At rest, the inside of a neuron's membrane is more negative than the outside.

Which of the following is the correct order of transmission of information within a neuron?

The sodium-potassium pump pumps sodium ions ____ and potassium ions ____.

Which of the following is NOT true for sodium ions when the cell is at resting potential?

Prior to the work of Santiago Ramon y Cajal, what did many investigators believe?

Why does the brain need thiamine?

The general rule among neurons is that the wider the branching, the fewer connections with other neurons.

Which of these is true of glial cells?

Which of the following is most likely to cross the cell membrane by simple diffusion?

Which of the following is TRUE of local neurons?

The difference in voltage in a resting neuron is called the resting potential.

Which of the following events would increase the concentration gradient of sodium?

If a drug was given that temporarily inactivated the sodium-potassium pumps, action potentials would cease immediately.

Of the following, the most important consideration in developing a drug that will act in the brain is:

According to the all-or-none law:

The Major Issues

Synapses

Anatomy of the Nervous System

Development and Plasticity of the Brain

Vision

The Other Sensory Systems

Movement

Wakefulness and Sleep

Internal Regulation

Reproductive Behaviors

Emotional Behaviors

The Biology of Learning and Memory

Cognitive Functions

Mood Disorders and Schizophrenia

Filters

The sodium-potassium pump pumps sodium ions and potassium ions .