Question 1

Depolarization occurs due to the diffusion of K+across a neuron plasma membrane.

Accepted Answer

A) True 
 B)False

Question 2

If a drug inhibits the uptake of an excitatory neurotransmitter after it has been released into the synaptic cleft, what is the most likely result?

Accepted Answer

A)  an increased number of IPSPs 
B)  an increased number of EPSPs 
C)  a prolonged hyperpolarization 
D)  a decreased number of IPSPs 
E)  a decreased number of EPSPs 
A)  an increased number of IPSPs 
B)  an increased number of EPSPs 
C)  a prolonged hyperpolarization 
D)  a decreased number of IPSPs 
E)  a decreased number of EPSPs

Question 3

Neurotransmitters are stored in vesicles located within axon terminals .

Accepted Answer

A) True 
 B)False

Question 4

If a drug binds to a receptor, which normally triggers the opening of a Na+channel, causing it to open in the absence of neurotransmitter release, what is the most likely result?

Accepted Answer

A)  an increased number of IPSPs 
B)  an increased number of EPSPs 
C)  a prolonged hyperpolarization 
D)  a decreased number of IPSPs 
E)  a decreased number of EPSPs 
A)  an increased number of IPSPs 
B)  an increased number of EPSPs 
C)  a prolonged hyperpolarization 
D)  a decreased number of IPSPs 
E)  a decreased number of EPSPs

Question 5

When a neuron membrane potential goes below its resting value it becomes ____.

Accepted Answer

A)  depolarized 
B)  hyperpolarized 
C)  repolarized 
D)  damaged 
E)  restimulated 
A)  depolarized 
B)  hyperpolarized 
C)  repolarized 
D)  damaged 
E)  restimulated

Question 6

For a neuron at rest, there is a higher concentration of ____ outside the cell than inside.

Accepted Answer

A)  Na+ 
B)  K+ 
C)  Ca2+ 
D)  anions 
E)  ATP 
A)  Na+ 
B)  K+ 
C)  Ca2+ 
D)  anions 
E)  ATP

Question 7

Figure 39.1
-
Answer the question using the accompanying figure. At which point in this action potential diagram are Na+inactivation gates opening?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 8

In an electrical synapse, an electrical signal is communicated between two cells via ____ through ____.

Accepted Answer

A)  ion flow; the synaptic cleft 
B)  neurotransmitter flow; the synaptic cleft 
C)  neurotransmitter flow; gap junctions 
D)  ion flow; gap junctions 
E)  exocytosis; the plasma membrane 
A)  ion flow; the synaptic cleft 
B)  neurotransmitter flow; the synaptic cleft 
C)  neurotransmitter flow; gap junctions 
D)  ion flow; gap junctions 
E)  exocytosis; the plasma membrane

Question 9

What characterizes projection neurons?

Accepted Answer

A)  forming many branches near the tip 
B)  communicating with other nearby neurons 
C)  Axons extending far from the cell body 
D)  forming many branches near the cell body 
E)  both forming many branches near the tip and axons extending far from the cell body 
A)  forming many branches near the tip 
B)  communicating with other nearby neurons 
C)  Axons extending far from the cell body 
D)  forming many branches near the cell body 
E)  both forming many branches near the tip and axons extending far from the cell body

Question 10

When an action potential reaches the axon terminal, the ____ channels are activated to trigger synaptic vesicle release.

Accepted Answer

A)  voltage-gated Cl-channels 
B)  voltage-gated Ca2+channels 
C)  voltage-gated Na+channels 
D)  ligand-gated Cl-channels 
E)  ligand-gated Ca2+channels 
A)  voltage-gated Cl-channels 
B)  voltage-gated Ca2+channels 
C)  voltage-gated Na+channels 
D)  ligand-gated Cl-channels 
E)  ligand-gated Ca2+channels

Question 11

The Nernst equation is used to calculate the ____.

Accepted Answer

A)  action potential 
B)  equilibrium potential 
C)  membrane potential of a neuron at rest 
D)  membrane potential of a hyperpolarized neuron 
E)  membrane potential of a depolarized neuron 
A)  action potential 
B)  equilibrium potential 
C)  membrane potential of a neuron at rest 
D)  membrane potential of a hyperpolarized neuron 
E)  membrane potential of a depolarized neuron

Question 12

The minimum level of depolarization required to initiate an action potential in an excitable cell is called the ____ potential.

Accepted Answer

A)  electrical 
B)  refractory 
C)  membrane 
D)  resting 
E)  threshold 
A)  electrical 
B)  refractory 
C)  membrane 
D)  resting 
E)  threshold

Question 13

Calculate ENafor a neuron that has an extracellular concentration of Na+of 78 mM and an intracellular concentration of Na+of 6 mM.

Accepted Answer

A)  -68.0 mV 
B)  -1.14 mV 
C)  1.14 mV 
D)  31.6 mV 
E)  68.0 mV 
A)  -68.0 mV 
B)  -1.14 mV 
C)  1.14 mV 
D)  31.6 mV 
E)  68.0 mV

Question 14

The binding of a neurotransmitter to ligand-gated K+channels will cause ____ in the postsynaptic membrane.

Accepted Answer

A)  depolarization only 
B)  hyperpolarization 
C)  repolarization only 
D)  apolarization 
E)  depolarization and repolarization 
A)  depolarization only 
B)  hyperpolarization 
C)  repolarization only 
D)  apolarization 
E)  depolarization and repolarization

Question 15

What will be the effect of a drug that prevents the release of intracellular calcium?

Accepted Answer

A)  a decreased number of IPSPs 
B)  a decreased number of EPSPs 
C)  a prolonged hyperpolarization 
D)  increased neurotransmitter release 
E)  decreased neurotransmitter release 
A)  a decreased number of IPSPs 
B)  a decreased number of EPSPs 
C)  a prolonged hyperpolarization 
D)  increased neurotransmitter release 
E)  decreased neurotransmitter release

Question 16

The binding of a neurotransmitter to ligand-gated Na+channels will cause ____ in the postsynaptic membrane.

Accepted Answer

A)  depolarization only 
B)  hyperpolarization 
C)  repolarization only 
D)  apolarization 
E)  depolarization and repolarization 
A)  depolarization only 
B)  hyperpolarization 
C)  repolarization only 
D)  apolarization 
E)  depolarization and repolarization

Question 17

Saltatory conduction is the slowest form of action potential propagation.

Accepted Answer

A) True 
 B)False

Question 18

During an action potential, the membrane potential can reach as high as ____.

Accepted Answer

A)  -10 mV 
B)  0 mV 
C)  +10 mV 
D)  +20 mV 
E)  +30 mV 
A)  -10 mV 
B)  0 mV 
C)  +10 mV 
D)  +20 mV 
E)  +30 mV

Question 19

The magnitude of an action potential ____ as it is propagated down an excitable membrane due to the ____ principle.

Accepted Answer

A)  increases; all-or-nothing 
B)  remains constant; all-or-nothing 
C)  increases; threshold 
D)  remains constant; threshold 
A)  increases; all-or-nothing 
B)  remains constant; all-or-nothing 
C)  increases; threshold 
D)  remains constant; threshold

Question 20

At which neuronal structure does summation occur?

Accepted Answer

A)  dendrites 
B)  cell body 
C)  axon hillock 
D)  Schwann cells 
E)  axon terminals 
A)  dendrites 
B)  cell body 
C)  axon hillock 
D)  Schwann cells 
E)  axon terminals

Exam 39: Information Flow and the Neuron

Depolarization occurs due to the diffusion of K+across a neuron plasma membrane.

If a drug inhibits the uptake of an excitatory neurotransmitter after it has been released into the synaptic cleft, what is the most likely result?

Neurotransmitters are stored in vesicles located within axon terminals .

If a drug binds to a receptor, which normally triggers the opening of a Na+channel, causing it to open in the absence of neurotransmitter release, what is the most likely result?

When a neuron membrane potential goes below its resting value it becomes ____.

For a neuron at rest, there is a higher concentration of ____ outside the cell than inside.

Figure 39.1 - Answer the question using the accompanying figure. At which point in this action potential diagram are Na+inactivation gates opening?

In an electrical synapse, an electrical signal is communicated between two cells via ____ through ____.

What characterizes projection neurons?

When an action potential reaches the axon terminal, the ____ channels are activated to trigger synaptic vesicle release.

The Nernst equation is used to calculate the ____.

The minimum level of depolarization required to initiate an action potential in an excitable cell is called the ____ potential.

Calculate ENafor a neuron that has an extracellular concentration of Na+of 78 mM and an intracellular concentration of Na+of 6 mM.

The binding of a neurotransmitter to ligand-gated K+channels will cause ____ in the postsynaptic membrane.

What will be the effect of a drug that prevents the release of intracellular calcium?

The binding of a neurotransmitter to ligand-gated Na+channels will cause ____ in the postsynaptic membrane.

Saltatory conduction is the slowest form of action potential propagation.

During an action potential, the membrane potential can reach as high as ____.

The magnitude of an action potential ____ as it is propagated down an excitable membrane due to the ____ principle.

At which neuronal structure does summation occur?

Introduction to Biological Concepts and Research

Life, Chemistry, and Water

Biological Molecules: the Carbon Compounds of Life

Cells

Membranes and Transport

Energy, Enzymes, and Biological Reactions

Cellular Respiration: Harvesting Chemical Energy

Photosynthesis

Cell Communication

Cell Division and Mitosis

Meiosis: the Cellular Basis of Sexual Reproduction

Mendel, Genes, and Inheritance

Genes, Chromosomes, and Human Genetics

Dna Structure, Replication, and Organization

Gene Expression: From Dna to Protein

Regulation of Gene Expression

Bacterial and Viral Genetics

Dna Technology: Making and Using Genetically Altered Organisms, and Other Applications

Genomes and Proteomes

The Development of Evolutionary Thought

Microevolution: Genetic Changes Within Populations

Speciation

Paleobiology and Macroevolution

Systematic Biology: Phylogeny and Classification

The Origin of Life

Prokaryotes and Viruses

Protists

Seedless Plants

Seed Plants

Fungi

Animal Phylogeny, Acoelomates, and Protostomes

Deuterostomes: Vertebrates and Their Closest Relatives

The Plant Body

Transport in Plants

Plant Nutrition

Reproduction and Development in Flowering Plants

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Nervous Systems

Sensory Systems

The Endocrine System

Muscles, Bones, and Body Movements

The Circulatory System

Defenses Against Disease

Gas Exchange: the Respiratory System

Digestive Systems and Animal Nutrition

Regulating the Internal Environment: Osmoregulation, Excretion, and Thermoregulation

Animal Reproduction

Animal Development

Ecology and the Biosphere

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Biodiversity and Conservation Biology

Animal Behavior

Filters

Depolarization occurs due to the diffusion of K⁺across a neuron plasma membrane.

If a drug binds to a receptor, which normally triggers the opening of a Na⁺channel, causing it to open in the absence of neurotransmitter release, what is the most likely result?

Figure 39.1 - Answer the question using the accompanying figure. At which point in this action potential diagram are Na⁺inactivation gates opening?

In an electrical synapse, an electrical signal is communicated between two cells via through .

Calculate E_Nafor a neuron that has an extracellular concentration of Na⁺of 78 mM and an intracellular concentration of Na⁺of 6 mM.

The binding of a neurotransmitter to ligand-gated K⁺channels will cause ____ in the postsynaptic membrane.

The binding of a neurotransmitter to ligand-gated Na⁺channels will cause ____ in the postsynaptic membrane.

The magnitude of an action potential as it is propagated down an excitable membrane due to the principle.