Question 1

At which of the following neuron locations does summation occur?

Accepted Answer

A) at the dendrites 
B) at the axon hillock 
C) at the axon terminals 
D) at the cell body 
A) at the dendrites 
B) at the axon hillock 
C) at the axon terminals 
D) at the cell body B

Question 2

What happens to the magnitude of an action potential as it is propagated down an excitable membrane and why?

Accepted Answer

A) It increases because it is a threshold principle. 
B) It increases because it is an all-or-nothing principle. 
C) It remains constant because it is an all-or-nothing principle. 
D) It remains constant because it is a threshold principle. 
A) It increases because it is a threshold principle. 
B) It increases because it is an all-or-nothing principle. 
C) It remains constant because it is an all-or-nothing principle. 
D) It remains constant because it is a threshold principle. C

Question 3

A toxin interferes with the opening of Na+ channels in the postsynaptic membrane so that they open more slowly when bound to a neurotransmitter. What effect would there be on action potential formation in the postsynaptic membrane?

Accepted Answer

This would cause a postsynaptic membrane action potential to form more slowly (if at all), as well as slow the action potential propagation speed.

Question 4

What can the neurotransmitter acetylcholine in vertebrates do?

Accepted Answer

A) be released into circulation and act as a hormone 
B) make it more difficult for some presynaptic membranes to reach threshold 
C) act as a direct neurotransmitter between neurons and muscle cells 
D) be released into circulation and act as an enzyme 
A) be released into circulation and act as a hormone 
B) make it more difficult for some presynaptic membranes to reach threshold 
C) act as a direct neurotransmitter between neurons and muscle cells 
D) be released into circulation and act as an enzyme

Question 5

Match each term with its description.
-membrane potential

Accepted Answer

A) electrical potential difference across a plasma membrane 
B) subthreshold change in membrane potential toward the threshold potential of a neuron 
C) membrane potential of an excitable membrane when it is not being stimulated 
D) subthreshold change in membrane potential away from the threshold potential of a neuron 
E) abrupt, transient change in membrane potential, consisting of membrane depolarization followed by repolarization
F)minimum membrane potential required to form an action potential
G)any subthreshold change in membrane potential whose effects are additive 
A) electrical potential difference across a plasma membrane 
B) subthreshold change in membrane potential toward the threshold potential of a neuron 
C) membrane potential of an excitable membrane when it is not being stimulated 
D) subthreshold change in membrane potential away from the threshold potential of a neuron 
E) abrupt, transient change in membrane potential, consisting of membrane depolarization followed by repolarization
F)minimum membrane potential required to form an action potential
G)any subthreshold change in membrane potential whose effects are additive

Question 6

Match each term with its definition.
-nerve net

Accepted Answer

A) loose meshwork of neurons organized with radial symmetry 
B) cavities in the vertebrate brain filled with cerebrospinal fluid 
C) efferent portion of the PNS that deals with body movements that are under conscious, voluntary control 
D) neuronal activity that occurs without conscious effort; often associated with protection 
E) carries nervous activity from the brain and spinal cord to effector structures
F)composed of the midbrain, pons, and medulla
G)import with the ability to speak 
A) loose meshwork of neurons organized with radial symmetry 
B) cavities in the vertebrate brain filled with cerebrospinal fluid 
C) efferent portion of the PNS that deals with body movements that are under conscious, voluntary control 
D) neuronal activity that occurs without conscious effort; often associated with protection 
E) carries nervous activity from the brain and spinal cord to effector structures
F)composed of the midbrain, pons, and medulla
G)import with the ability to speak

Question 7

Invertebrates, such as the flatworm, have groups of neurons with a common function. What is the name of these nerve clusters?

Accepted Answer

A) the spine 
B) the brain 
C) nerve cords 
D) ganglia 
A) the spine 
B) the brain 
C) nerve cords 
D) ganglia

Question 8

Match each term with its description.
-IPSP

Accepted Answer

A) electrical potential difference across a plasma membrane 
B) subthreshold change in membrane potential toward the threshold potential of a neuron 
C) membrane potential of an excitable membrane when it is not being stimulated 
D) subthreshold change in membrane potential away from the threshold potential of a neuron 
E) abrupt, transient change in membrane potential, consisting of membrane depolarization followed by repolarization
F)minimum membrane potential required to form an action potential
G)any subthreshold change in membrane potential whose effects are additive 
A) electrical potential difference across a plasma membrane 
B) subthreshold change in membrane potential toward the threshold potential of a neuron 
C) membrane potential of an excitable membrane when it is not being stimulated 
D) subthreshold change in membrane potential away from the threshold potential of a neuron 
E) abrupt, transient change in membrane potential, consisting of membrane depolarization followed by repolarization
F)minimum membrane potential required to form an action potential
G)any subthreshold change in membrane potential whose effects are additive

Question 9

What organic macromolecules allow myelinated sheaths to act as electrical insulators?

Accepted Answer

A) proteins 
B) lipids 
C) carbohydrates 
D) nucleic acids 
A) proteins 
B) lipids 
C) carbohydrates 
D) nucleic acids

Question 10

Match each term with its description.
-EPSP

Accepted Answer

A) electrical potential difference across a plasma membrane 
B) subthreshold change in membrane potential toward the threshold potential of a neuron 
C) membrane potential of an excitable membrane when it is not being stimulated 
D) subthreshold change in membrane potential away from the threshold potential of a neuron 
E) abrupt, transient change in membrane potential, consisting of membrane depolarization followed by repolarization
F)minimum membrane potential required to form an action potential
G)any subthreshold change in membrane potential whose effects are additive 
A) electrical potential difference across a plasma membrane 
B) subthreshold change in membrane potential toward the threshold potential of a neuron 
C) membrane potential of an excitable membrane when it is not being stimulated 
D) subthreshold change in membrane potential away from the threshold potential of a neuron 
E) abrupt, transient change in membrane potential, consisting of membrane depolarization followed by repolarization
F)minimum membrane potential required to form an action potential
G)any subthreshold change in membrane potential whose effects are additive

Question 11

-When comparing electrical synapses and chemical synapses in the figure, what structures are found only in electrical synapses?

Accepted Answer

A) synaptic clefts 
B) gap junctions 
C) neurotransmitters 
D) postsynaptic plasma cell receptors 
A) synaptic clefts 
B) gap junctions 
C) neurotransmitters 
D) postsynaptic plasma cell receptors

Question 12

Which of the following can be found in higher concentrations on the outside of a neuron's plasma membrane relative to the inside?

Accepted Answer

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

Question 13

Explain how the resting membrane potential and resting ion distributions are established in a neuron.

Accepted Answer

A resting membrane potential of -70 mV i

Question 14

Which term refers to the minimum level of depolarization required to initiate an action potential in an excitable cell?

Accepted Answer

A) membrane potential 
B) refractory potential 
C) electrical potential 
D) threshold potential 
A) membrane potential 
B) refractory potential 
C) electrical potential 
D) threshold potential

Question 15

Match each situation to the most appropriate term.
-is the phase of an action potential when the membrane potential becomes more positive

Accepted Answer

A) depolarization 
B) repolarization 
C) hyperpolarization 
A) depolarization 
B) repolarization 
C) hyperpolarization

Question 16

Which of the following assist and nourish cells that transmit electrical signals?

Accepted Answer

A) glial cells 
B) effector cells 
C) receptors 
D) neurons 
A) glial cells 
B) effector cells 
C) receptors 
D) neurons

Question 17

Which cells are located in the brain and spinal cord of vertebrates?

Accepted Answer

A) afferent neurons 
B) efferent neurons 
C) motor neurons 
D) interneurons 
A) afferent neurons 
B) efferent neurons 
C) motor neurons 
D) interneurons

Question 18

What type of neuron directly stimulates a muscle or gland?

Accepted Answer

A) an interneuron 
B) an afferent neuron 
C) a sensory neuron 
D) an efferent neuron 
A) an interneuron 
B) an afferent neuron 
C) a sensory neuron 
D) an efferent neuron

Question 19

Which of the following neuron locations have the greatest density of voltage-gated Na+ channels, thus resulting in the lowest threshold potential along a neuron?

Accepted Answer

A) the axon terminals 
B) the cell bodies 
C) the dendrites 
D) the axon hillocks 
A) the axon terminals 
B) the cell bodies 
C) the dendrites 
D) the axon hillocks

Question 20

-In the action potential diagram, at what point are Na+ inactivation gates opening and K+ activation gates closing?

Accepted Answer

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

Exam 44: Control of Animal Processes: Neural Control

At which of the following neuron locations does summation occur?

What happens to the magnitude of an action potential as it is propagated down an excitable membrane and why?

A toxin interferes with the opening of Na+ channels in the postsynaptic membrane so that they open more slowly when bound to a neurotransmitter. What effect would there be on action potential formation in the postsynaptic membrane?

What can the neurotransmitter acetylcholine in vertebrates do?

Match each term with its description. -membrane potential

Match each term with its definition. -nerve net

Invertebrates, such as the flatworm, have groups of neurons with a common function. What is the name of these nerve clusters?

Match each term with its description. -IPSP

What organic macromolecules allow myelinated sheaths to act as electrical insulators?

Match each term with its description. -EPSP

-When comparing electrical synapses and chemical synapses in the figure, what structures are found only in electrical synapses?

Which of the following can be found in higher concentrations on the outside of a neuron's plasma membrane relative to the inside?

Explain how the resting membrane potential and resting ion distributions are established in a neuron.

Which term refers to the minimum level of depolarization required to initiate an action potential in an excitable cell?

Match each situation to the most appropriate term. -is the phase of an action potential when the membrane potential becomes more positive

Which of the following assist and nourish cells that transmit electrical signals?

Which cells are located in the brain and spinal cord of vertebrates?

What type of neuron directly stimulates a muscle or gland?

Which of the following neuron locations have the greatest density of voltage-gated Na+ channels, thus resulting in the lowest threshold potential along a neuron?

-In the action potential diagram, at what point are Na+ inactivation gates opening and K+ activation gates closing?

Light and Life

The Cell: an Overview

Defining Life and Its Origins

Energy and Enzymes

Cell Membranes and Signalling

Cellular Respiration

Photosynthesis

Cell Cycles

Genetic Recombination

Mendel, Genes, and Inheritance

Genes, Chromosomes, and Human Genetics

Dna Structure, Replication, and Organization

Gene Structure and Expression

Control of Gene Expression

Dna Technologies

Genomes and Proteomes

Evolution: the Development of the Theory

Microevolution: Changes Within Populations

Species and Macroevolution

Understanding the History of Life on Earth

Humans and Evolution

Bacteria and Archaea

Viruses, Viroids, and Prions: Infectious Biological Particles

Protists

Fungi

Plants

Diversity of Animals 1: Sponges, Radiata, Platyhelminthes, and Protostomes

Diversity of Animals 2: Deuterostomes: Vertebrates and Their Closest Relatives

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Conservation of Biodiversity

Putting Selection to Work

Organization of the Plant Body

Transport in Plants

Reproduction and Development in Flowering Plants

Plant Nutrition

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Transport in Animals: the Circulatory System

Reproduction in Animals

Animal Development

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Integration

Muscles, Skeletons, and Body Movements

Animal Behaviour

Animal Nutrition

Gas Exchange: the Respiratory System

Regulating the Internal Environment

Defences Against Disease

Conservation and Evolutionary Physiology

Filters

A toxin interferes with the opening of Na⁺ channels in the postsynaptic membrane so that they open more slowly when bound to a neurotransmitter. What effect would there be on action potential formation in the postsynaptic membrane?

Which of the following neuron locations have the greatest density of voltage-gated Na⁺ channels, thus resulting in the lowest threshold potential along a neuron?

-In the action potential diagram, at what point are Na⁺ inactivation gates opening and K⁺ activation gates closing?