Question 1

Describe the startle response in the cockroach.

Accepted Answer

The cockroach's startle response is a re

Question 2

Myelination by Schwann cells increases the velocity of action potential propagation by

Accepted Answer

A)  increasing the resistance and decreasing the capacitance, allowing the action potential to "jump" over the myelinated area. 
B)  decreasing the resistance and increasing the capacitance, allowing the action potential to "jump" over the myelinated area. 
C)  increasing the resistance and increasing the capacitance, allowing the action potential to "jump" over the myelinated area. 
D)  increasing the diameter of the neuron. 
A)  increasing the resistance and decreasing the capacitance, allowing the action potential to "jump" over the myelinated area. 
B)  decreasing the resistance and increasing the capacitance, allowing the action potential to "jump" over the myelinated area. 
C)  increasing the resistance and increasing the capacitance, allowing the action potential to "jump" over the myelinated area. 
D)  increasing the diameter of the neuron.

Question 3

Conduction velocity shows _______ axon diameter.

Accepted Answer

A)  a proportional relationship to 
B)  a proportional relationship to the square root of 
C)  an exponential relationship to 
D)  either a proportional relationship to, or a proportional relationship to the square root of 
A)  a proportional relationship to 
B)  a proportional relationship to the square root of 
C)  an exponential relationship to 
D)  either a proportional relationship to, or a proportional relationship to the square root of

Question 4

Which statement about an animal's nervous system is true?

Accepted Answer

A)  Neurotransmitter is released throughout the body via the blood. 
B)  Signal transmission rate is relatively slow. 
C)  Neurons form highly discrete lines of communication. 
D)  Action potential signals degrade over distance. 
A)  Neurotransmitter is released throughout the body via the blood. 
B)  Signal transmission rate is relatively slow. 
C)  Neurons form highly discrete lines of communication. 
D)  Action potential signals degrade over distance.

Question 5

Refer to the figure shown.
  Which statement about ion permeability as shown in the figure is true?

Accepted Answer

A)  K+ permeability is at its lowest very close to the membrane potential peak. 
B)  K+ permeability is at its highest very close to the membrane potential peak. 
C)  Na+ permeability is at its lowest very close to the membrane potential peak. 
D)  Na+ permeability is at its highest very close to the membrane potential peak. 
A)  K+ permeability is at its lowest very close to the membrane potential peak. 
B)  K+ permeability is at its highest very close to the membrane potential peak. 
C)  Na+ permeability is at its lowest very close to the membrane potential peak. 
D)  Na+ permeability is at its highest very close to the membrane potential peak.

Question 6

What are glial cells and how do they aid in the function of the nervous system?

Accepted Answer

Glial cells are the support cells of the

Question 7

Refer to the figure shown.
  What occurs when the membrane is clamped at -100 mV?

Accepted Answer

A)  Voltage-gated ion channels behave in a similar manner as in the diagram. 
B)  Voltage-gated ion channels do not open at all. 
C)  There is a brief shift in ions and then a flat current at -100 mV. 
D)  Only ligand-gated channels work at this point. 
A)  Voltage-gated ion channels behave in a similar manner as in the diagram. 
B)  Voltage-gated ion channels do not open at all. 
C)  There is a brief shift in ions and then a flat current at -100 mV. 
D)  Only ligand-gated channels work at this point.

Question 8

Refer to the figure shown.
  Which arrow best represents the point where the voltage-gated sodium channels are inactivated?

Accepted Answer

A)  I 
B)  III 
C)  IV 
D)  III and IV 
A)  I 
B)  III 
C)  IV 
D)  III and IV

Question 9

Since the bulk solutions that make up the intracellular and extracellular fluids maintain charge neutrality, how does the cell produce membrane potentials?

Accepted Answer

The charge separation producing the memb

Question 10

Refer to the figure shown.
  What would likely occur if stimulus 3 and 6 were performed simultaneously?

Accepted Answer

A)  An action potential would likely occur. 
B)  An action potential would likely not occur. 
C)  Multiple action potentials would likely occur. 
D)  The threshold voltage would likely decrease. 
A)  An action potential would likely occur. 
B)  An action potential would likely not occur. 
C)  Multiple action potentials would likely occur. 
D)  The threshold voltage would likely decrease.

Question 11

Which statement about membrane capacitance is true?

Accepted Answer

A)  It is in series with membrane resistance. 
B)  In a cell, the membrane separates only similarly charged ions. 
C)  It is measured in ohms. 
D)  It is a function of the permeability of the membrane. 
A)  It is in series with membrane resistance. 
B)  In a cell, the membrane separates only similarly charged ions. 
C)  It is measured in ohms. 
D)  It is a function of the permeability of the membrane.

Question 12

Refer to the figure shown.
  The treatment difference between the membranes shown in the graphs is that the membrane on the left is being _______, while the membrane on the right is being _______.

Accepted Answer

A)  depolarized; depolarized in Na+-free seawater 
B)  hyperpolarized; hyperpolarized in an isoionic Na+ solution 
C)  hyperpolarized; depolarized 
D)  depolarized; hyperpolarized 
A)  depolarized; depolarized in Na+-free seawater 
B)  hyperpolarized; hyperpolarized in an isoionic Na+ solution 
C)  hyperpolarized; depolarized 
D)  depolarized; hyperpolarized

Question 13

Explain in mechanistic terms how the action potential is an all-or-none phenomenon.

Accepted Answer

The action potential is initiated only w

Question 14

Which statement about glial cells is true?

Accepted Answer

A)  They integrate cell membrane potentials to enhance or inhibit action potentials. 
B)  They decrease the velocity of nerve-impulse propagation. 
C)  They help supply metabolic substrates to neurons. 
D)  They act as metabolic intermediaries between epithelial cells and neurons. 
A)  They integrate cell membrane potentials to enhance or inhibit action potentials. 
B)  They decrease the velocity of nerve-impulse propagation. 
C)  They help supply metabolic substrates to neurons. 
D)  They act as metabolic intermediaries between epithelial cells and neurons.

Question 15

Which statement about a voltage clamp of a neuron at 0 mV is true?

Accepted Answer

A)  Once clamped, the membrane depolarizes then returns to resting potential. 
B)  Voltage-gated potassium channels open. 
C)  Apart from the initial current shift from the clamp, no other current is produced. 
D)  Voltage-gated sodium channels close 
A)  Once clamped, the membrane depolarizes then returns to resting potential. 
B)  Voltage-gated potassium channels open. 
C)  Apart from the initial current shift from the clamp, no other current is produced. 
D)  Voltage-gated sodium channels close

Question 16

Which variable does not contribute to the passive electrical properties of a cell?

Accepted Answer

A)  Membrane resistance 
B)  Membrane capacitance 
C)  The resting membrane current 
D)  The time constant 
A)  Membrane resistance 
B)  Membrane capacitance 
C)  The resting membrane current 
D)  The time constant

Question 17

Initiation of the action potential usually occurs _______ of the neuron.

Accepted Answer

A)  in the cell body 
B)  on the dendrites 
C)  at the axon initial segment 
D)  on the axon 
A)  in the cell body 
B)  on the dendrites 
C)  at the axon initial segment 
D)  on the axon

Question 18

Which characteristic is not a factor in the Nernst Equation?

Accepted Answer

A)  Capacitance 
B)  Temperature 
C)  The valence of the ion species 
D)  The ion concentrations on the two sides of the membrane 
A)  Capacitance 
B)  Temperature 
C)  The valence of the ion species 
D)  The ion concentrations on the two sides of the membrane

Question 19

Refer to the figure shown.
  What is occurring at the membrane?

Accepted Answer

A)  Depolarization 
B)  Hyperpolarization 
C)  Increase in resistance 
D)  Decrease in capacitance 
A)  Depolarization 
B)  Hyperpolarization 
C)  Increase in resistance 
D)  Decrease in capacitance

Question 20

Refer to the figure shown.
  What is the best explanation for the plateau shown in the figure?

Accepted Answer

A)  Voltage-gated Na+ channels remain open. 
B)  Voltage-gated Ca2+ channels remain open. 
C)  Voltage-gated K+ channels close. 
D)  Leaky K+ channels remain open. 
A)  Voltage-gated Na+ channels remain open. 
B)  Voltage-gated Ca2+ channels remain open. 
C)  Voltage-gated K+ channels close. 
D)  Leaky K+ channels remain open.

Exam 12: Neurons

Describe the startle response in the cockroach.

Myelination by Schwann cells increases the velocity of action potential propagation by

Conduction velocity shows _______ axon diameter.

Which statement about an animal's nervous system is true?

Refer to the figure shown. Which statement about ion permeability as shown in the figure is true?

What are glial cells and how do they aid in the function of the nervous system?

Refer to the figure shown. What occurs when the membrane is clamped at -100 mV?

Refer to the figure shown. Which arrow best represents the point where the voltage-gated sodium channels are inactivated?

Since the bulk solutions that make up the intracellular and extracellular fluids maintain charge neutrality, how does the cell produce membrane potentials?

Refer to the figure shown. What would likely occur if stimulus 3 and 6 were performed simultaneously?

Which statement about membrane capacitance is true?

Refer to the figure shown. The treatment difference between the membranes shown in the graphs is that the membrane on the left is being _______, while the membrane on the right is being _______.

Explain in mechanistic terms how the action potential is an all-or-none phenomenon.

Which statement about glial cells is true?

Which statement about a voltage clamp of a neuron at 0 mV is true?

Which variable does not contribute to the passive electrical properties of a cell?

Initiation of the action potential usually occurs _______ of the neuron.

Which characteristic is not a factor in the Nernst Equation?

Refer to the figure shown. What is occurring at the membrane?

Refer to the figure shown. What is the best explanation for the plateau shown in the figure?

Animals and Environments: Function on the Ecological Stage

Molecules and Cells in Animal Physiology

Genomics, Proteomics, and Related Approaches to Physiology

Physiological Development and Epigenetics

Transport of Solutes and Water

Nutrition, Feeding, and Digestion

Energy Metabolism

Aerobic and Anaerobic Forms of Metabolism

The Energetics of Aerobic Activity

Thermal Relations

Food, Energy, and Temperature at Work: The Lives of Mammals in Frigid Places

Synapses

Sensory Processes

Nervous System Organization and Biological Clocks

Endocrine and Neuroendocrine Physiology

Reproduction

Integrating Systems at Work: Animal Navigation

Control of Movement

Muscle

Movement and Muscle at Work: Plasticity in Response to Use and Disuse

Introduction to Oxygen and Carbon Dioxide in Physiology

External Respiration: the Physiology of Breathing

Transport of Oxygen and Carbon Dioxide in Body Fluids With an Introduction to Acid- Base Physiology

Circulation

Oxygen, Carbon Dioxide, and Internal Transport at Work: Diving by Marine Mammals

Water and Salt Physiology: Introduction and Mechanisms

Kidneys and Excretion With Notes on Nitrogen Excretion

Water, Salts, and Excretion at Work: Mammals of Deserts and Dry Savannas

Water and Salt Physiology of Animals in Their Environments

Filters

Refer to the figure shown. The treatment difference between the membranes shown in the graphs is that the membrane on the left is being _, while the membrane on the right is being _.