Question 1

The absolute refractory period of an action potential

Accepted Answer

A)  only ensures one-way travel down an axon. 
B)  only allows a neuron to ignore a second signal sent that closely follows the first. 
C)  only prevents summation of action potentials. 
D)  ensures one-way travel down an axon and allows a neuron to ignore a second signal sent that closely follows the first. 
E)  ensures one-way travel down an axon, allows a neuron to ignore a second signal sent that closely follows the first, and prevents summation of action potentials. 
A)  only ensures one-way travel down an axon. 
B)  only allows a neuron to ignore a second signal sent that closely follows the first. 
C)  only prevents summation of action potentials. 
D)  ensures one-way travel down an axon and allows a neuron to ignore a second signal sent that closely follows the first. 
E)  ensures one-way travel down an axon, allows a neuron to ignore a second signal sent that closely follows the first, and prevents summation of action potentials.

Question 2

Conduction speed is (or can be)enhanced by

Accepted Answer

A)  myelin. 
B)  altering extracellular sodium concentration. 
C)  increasing the temperature. 
D)  altering extracellular potassium concentration. 
E)  myelin and increasing the temperature. 
A)  myelin. 
B)  altering extracellular sodium concentration. 
C)  increasing the temperature. 
D)  altering extracellular potassium concentration. 
E)  myelin and increasing the temperature.

Question 3

The period of time during which an excitable membrane can respond again,but only if the stimulus is greater than the initial stimulus is the ________.

Accepted Answer

relative r

Question 4

When voltage-gated K+ channels of a resting neuron open,

Accepted Answer

A)  K+ enters the neuron. 
B)  K+ leaves the neuron. 
C)  the neuron depolarizes. 
D)  K+ enters the neuron and the neuron depolarizes. 
E)  K+ leaves the neuron and the neuron depolarizes. 
A)  K+ enters the neuron. 
B)  K+ leaves the neuron. 
C)  the neuron depolarizes. 
D)  K+ enters the neuron and the neuron depolarizes. 
E)  K+ leaves the neuron and the neuron depolarizes.

Question 5

Why is it necessary for fast axonal transport to go both forward and backward?

Accepted Answer

The organelles and cellular components t

Question 6

Glial cells

Accepted Answer

A)  only provide structural and metabolic support. 
B)  only guide neurons during growth and repair. 
C)  only help maintain homeostasis of the brain's extracellular fluid. 
D)  provide structural and metabolic support and help maintain homeostasis of the brain's extracellular fluid. 
E)  All of the answers are correct. 
A)  only provide structural and metabolic support. 
B)  only guide neurons during growth and repair. 
C)  only help maintain homeostasis of the brain's extracellular fluid. 
D)  provide structural and metabolic support and help maintain homeostasis of the brain's extracellular fluid. 
E)  All of the answers are correct.

Question 7

The afferent and efferent axons together form the

Accepted Answer

A)  central nervous system. 
B)  autonomic division system. 
C)  somatic motor division of the nervous system. 
D)  peripheral nervous system. 
E)  visceral nervous system. 
A)  central nervous system. 
B)  autonomic division system. 
C)  somatic motor division of the nervous system. 
D)  peripheral nervous system. 
E)  visceral nervous system.

Question 8

The brain and spinal cord together compose the

Accepted Answer

A)  central nervous system. 
B)  autonomic division system. 
C)  somatic motor division of the nervous system. 
D)  peripheral nervous system. 
E)  visceral nervous system. 
A)  central nervous system. 
B)  autonomic division system. 
C)  somatic motor division of the nervous system. 
D)  peripheral nervous system. 
E)  visceral nervous system.

Question 9

Briefly explain the gross organization of the nervous system in either paragraph form or using a concept map.Be sure to discuss the central,peripheral,and enteric nervous system and the divisions and branches discussed in the text.

Accepted Answer

Answers will vary.There are three divisi

Question 10

The basis of neural integration is

Accepted Answer

A)  addition of postsynaptic potentials overlapping in time and space. 
B)  command signals from central pattern generators. 
C)  spontaneous activity in pacemaker neurons. 
D)  the area under the curve of postsynaptic potentials overlapping in time and space. 
A)  addition of postsynaptic potentials overlapping in time and space. 
B)  command signals from central pattern generators. 
C)  spontaneous activity in pacemaker neurons. 
D)  the area under the curve of postsynaptic potentials overlapping in time and space.

Question 11

In terms of embryonic origin,neurons are most closely related to ________ cells.

Accepted Answer

A)  skeletal muscle 
B)  cardiac muscle 
C)  connective tissue 
D)  epithelial 
A)  skeletal muscle 
B)  cardiac muscle 
C)  connective tissue 
D)  epithelial

Question 12

The Nernst equation predicts

Accepted Answer

A)  intracellular ion concentrations. 
B)  extracellular ion concentrations 
C)  the membrane potential resulting from all permeable ions. 
D)  the membrane potential resulting from permeability to a single ion. 
E)  the threshold membrane potential. 
A)  intracellular ion concentrations. 
B)  extracellular ion concentrations 
C)  the membrane potential resulting from all permeable ions. 
D)  the membrane potential resulting from permeability to a single ion. 
E)  the threshold membrane potential.

Question 13

Calcium is important in the synapse because it

Accepted Answer

A)  is necessary for acetylcholine synthesis. 
B)  signals the exocytosis of the neurotransmitter. 
C)  binds to receptors on the postsynaptic cell, opening ion channels, and triggering graded potentials. 
D)  leaves the axon terminal, hyperpolarizing the cell. 
A)  is necessary for acetylcholine synthesis. 
B)  signals the exocytosis of the neurotransmitter. 
C)  binds to receptors on the postsynaptic cell, opening ion channels, and triggering graded potentials. 
D)  leaves the axon terminal, hyperpolarizing the cell.

Question 14

Receptors that work through second messenger systems are called ________ receptors.

Accepted Answer

The answer of Receptors that work through second messenger systems...

Question 15

The collection of axons that carries information between the central nervous system and the peripheral effectors is called the

Accepted Answer

A)  axon hillock. 
B)  varicosity. 
C)  axon. 
D)  dendrite. 
E)  nerve. 
A)  axon hillock. 
B)  varicosity. 
C)  axon. 
D)  dendrite. 
E)  nerve.

Question 16

When voltage-gated Na+ channels of a resting neuron open,

Accepted Answer

A)  Na+ enters the neuron. 
B)  Na+ leaves the neuron. 
C)  the neuron depolarizes. 
D)  Na+ enters the neuron and the neuron depolarizes. 
E)  Na+ leaves the neuron and the neuron depolarizes. 
A)  Na+ enters the neuron. 
B)  Na+ leaves the neuron. 
C)  the neuron depolarizes. 
D)  Na+ enters the neuron and the neuron depolarizes. 
E)  Na+ leaves the neuron and the neuron depolarizes.

Question 17

The minimum amount of stimulus required to depolarize an excitable membrane and generate an action potential is known as the ________.

Accepted Answer

The answer of The minimum amount of stimulus required to...

Question 18

Match the type of signal to its description (answers may be used more than once).
-originate(s)on dendrites and cell bodies

Accepted Answer

A) graded potential 
B) action potential 
C) both 
A) graded potential 
B) action potential 
C) both

Question 19

Dr.Zoydburger has discovered a toxin produced in the venom of a poisonous marine invertebrate.Tests on lab mammals indicate that this toxin prevents sodium channel inactivation.How would this affect the action potentials produced in the neurons of a poisoned mammal?

Accepted Answer

Without sodium channel inactivation,the

Question 20

A lab technician has inadvertently substituted lithium for sodium in a solution of saline for use by students in neurophysiology labs.If a frog nerve was bathed in this solution,what would happen upon stimulation of the nerve?

Accepted Answer

Assuming the specificity of the voltage-

Exam 8: Neurons: Cellular and Network Properties

The absolute refractory period of an action potential

Conduction speed is (or can be)enhanced by

The period of time during which an excitable membrane can respond again,but only if the stimulus is greater than the initial stimulus is the ________.

When voltage-gated K+ channels of a resting neuron open,

Why is it necessary for fast axonal transport to go both forward and backward?

Glial cells

The afferent and efferent axons together form the

The brain and spinal cord together compose the

Briefly explain the gross organization of the nervous system in either paragraph form or using a concept map.Be sure to discuss the central,peripheral,and enteric nervous system and the divisions and branches discussed in the text.

The basis of neural integration is

In terms of embryonic origin,neurons are most closely related to ________ cells.

The Nernst equation predicts

Calcium is important in the synapse because it

Receptors that work through second messenger systems are called ________ receptors.

The collection of axons that carries information between the central nervous system and the peripheral effectors is called the

When voltage-gated Na+ channels of a resting neuron open,

The minimum amount of stimulus required to depolarize an excitable membrane and generate an action potential is known as the ________.

Match the type of signal to its description (answers may be used more than once). -originate(s)on dendrites and cell bodies

Dr.Zoydburger has discovered a toxin produced in the venom of a poisonous marine invertebrate.Tests on lab mammals indicate that this toxin prevents sodium channel inactivation.How would this affect the action potentials produced in the neurons of a poisoned mammal?

A lab technician has inadvertently substituted lithium for sodium in a solution of saline for use by students in neurophysiology labs.If a frog nerve was bathed in this solution,what would happen upon stimulation of the nerve?

Introduction to Physiology

Molecular Interactions

Compartmentation: Cells and Tissues

Energy and Cellular Metabolism

Membrane Dynamics

Communication, Integration, and Homeostasis

Introduction to the Endocrine System

The Central Nervous System

Sensory Physiology

Efferent Division: Autonomic and Somatic Motor Control

Muscles

Integrative Physiology I: Control of Body Movement

Cardiovascular Physiology

Blood Flow and the Control of Blood Pressure

Blood

Mechanics of Breathing

Gas Exchange and Transport

The Kidneys

Integrative Physiology II: Fluid and Electrolyte Balance

The Digestive System

Metabolism and Energy Balance

Endocrine Control of Growth and Metabolism

The Immune System

Integrative Physiology III: Exercise

Reproduction and Development

Filters

When voltage-gated K⁺ channels of a resting neuron open,

When voltage-gated Na⁺ channels of a resting neuron open,