Deck 43: Control of Animal Processes: Neural Control

Question 1

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

A)Ca²⁺
B)Na⁺
C)K⁺
D)anions

Answer 1

B

Question 2

Which neurons are typically located in the peripheral nervous system?

A)spinal cord nerve cells
B)interneurons
C)brain nerve cells
D)motor neurons

Answer 2

D

Question 3

Which term refers to the component of a neural signalling pathway in which messages are sorted and interpreted?

A)integration
B)reception
C)response
D)action

Answer 3

A

Question 4

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

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

Question 5

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

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

Question 6

What nervous system cells send and receive electrical signals?

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

Question 7

Which of the following conduct(s) electrical signals away from the cell body of a neuron?

A)the dendrites
B)an axon terminal
C)an axon
D)the nucleus

Question 8

Which term refers to the spaces between adjacent Schwann cells?

A)nodes of Ranvier
B)axon terminals
C)active gaps
D)intercalated discs

Question 9

In the chemical synapse in the figure, which structure represents the synaptic cleft?

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

Question 10

Which structures are used by electrical synapses during signal transmission?

A)vesicles
B)neurotransmitters
C)Ca²⁺
D)gap junctions

Question 11

Which sequence places the components of a neural signalling pathway in the correct order, from beginning to end?

A)reception, integration, transmission, response
B)integration, transmission, reception, response
C)response, reception, transmission, integration
D)transmission, integration, reception, response

Question 12

What happens to a neuron's membrane when its membrane potential becomes less negative?

A)It becomes depolarized.
B)It becomes hyperpolarized.
C)It becomes hypopolarized.
D)It becomes repolarized.

Question 13

What is the typical resting potential of an isolated neuron?

A)-100 mV
B)-90 mV
C)-70 mV
D)-60 mV

Question 14

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

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

Question 15

Which of the following refers to an abrupt and transient change in membrane potential?

A)resting potential
B)refractory potential
C)action potential
D)threshold potential

Question 16

In the chemical synapse in the figure, which structure represents the axon terminal of a presynaptic cell?

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

Question 17

Which of the following is a component of neural signalling mechanisms?

A)integration
B)reaction
C)rejection
D)action

Question 18

Which of the following functions primarily in detecting and eliciting responses to environmental cues or stimuli?

A)the nervous system
B)the endocrine system
C)catabolism
D)metabolism

Question 19

In humans, which neurons are composed of the greatest number of cells?

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

Question 20

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

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

Question 21

Which of the following places the listed events of chemical synapse transmission in the correct order? 1
Ca²⁺ enters axon terminal.
2
Ligand-gated ion channels open in postsynaptic membrane.
3
Neurotransmitter binds to postsynaptic receptor.
4
Action potential reaches axon terminal of presynaptic neuron.
5
Neurotransmitter released by exocytosis.

A)4, 5, 2, 3, 1
B)4, 1, 5, 3, 2
C)4, 1, 3, 5, 2
D)4, 5, 1, 3, 2

Question 22

Why is an action potential propagated down an unmyelinated neuron plasma membrane?

A)because the action potential stimulates voltage-gated Cl^- channels adjacent to it
B)because the action potential stimulates voltage-gated Ca²⁺ channels adjacent to it
C)because the action potential stimulates voltage-gated Mg⁺ channels adjacent to it
D)because the action potential stimulates voltage-gated Na⁺ channels adjacent to it

Question 23

What happens to the neuron's membrane when its membrane potential goes below its resting value?

A)It becomes repolarized.
B)It becomes hyperpolarized.
C)It becomes hypopolarized.
D)It becomes depolarized.

Question 24

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

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

Question 25

Why is the refractory period of a neuron's plasma membrane important?

A)because it initiates an action potential
B)because it ensures that an impulse will travel in a one-way direction
C)because it ensures that the threshold potential will be reached
D)because it establishes the resting potential

Question 26

Which pair of ions is involved in changing membrane potential?

A)magnesium and potassium
B)sodium and magnesium
C)sodium and potassium
D)magnesium and chloride

Question 27

How is the intensity of an electrical impulse reflected?

A)in the magnitude of action potentials
B)in the frequency of action potentials
C)in the duration of action potentials
D)in the intensity of action potentials

Question 28

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

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.

Question 29

What happens as the action potential reaches its peak?

A)The inactivation gates of Na⁺ channels close.
B)The activation gates of Na⁺ channels close.
C)The inactivation gates of Na⁺ channels open.
D)Na⁺/K⁺ active transport pumps are activated.

Question 30

In the action potential diagram, at what point are many Na⁺ activation gates open and K⁺ activation gates closed?

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

Question 31

For which axon might you expect action potential propagation to be the fastest?

A)a myelinated axon with a large diameter
B)an unmyelinated axon with a small diameter
C)a myelinated axon with a small diameter
D)a myelinated axon of any diameter

Question 32

During an action potential, what level can the membrane potential reach?

A)as high as +70 mV
B)as high as +60 mV
C)as high as +50 mV
D)as high as +30 mV

Question 33

Why does depolarization of the neuron plasma membrane occur?

A)due to the diffusion of K⁺ into the cell
B)due to the diffusion of K⁺ out of the cell
C)due to the diffusion of Na⁺ out of the cell
D)due to the diffusion of Na⁺ into the cell

Question 34

What occurs when threshold potential is reached?

A)The activation gates of Na⁺ channels open.
B)The inactivation gates of Na⁺ channels open.
C)The activation gates of Na⁺ channels close.
D)Na⁺/K⁺ active transport pumps are activated.

Question 35

Which of the following remove(s) Ca²⁺ from the inside of an axon terminal of a chemical synapse after an electrical impulse has passed?

A)ion channels
B)simple diffusion through the plasma membrane
C)active transport pumps
D)exocytosis

Question 36

What would be disrupted if the K⁺ channels of an excitable plasma membrane were blocked by the action of a drug?

A)depolarization
B)repolarization
C)hyperpolarization
D)hypopolarization

Question 37

When are vesicles containing neurotransmitters released into the synaptic cleft?

A)when Ca²⁺ levels rise within the axon terminal
B)when Na⁺ levels rise within the axon terminal
C)when H⁺ levels rise within the axon terminal
D)when Cl- levels rise within the axon terminal

Question 38

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

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

Question 39

Which of the following is a reasonable estimation of the duration of an action potential?

A)approximately 5 microseconds
B)approximately 5 milliseconds
C)approximately 5 centiseconds
D)approximately 5 seconds

Question 40

Which structures aid in saltatory conduction?

A)nonmyelinated axons
B)synapses
C)myelinated axons
D)dendrites

Question 41

At which of the following neuron locations does summation occur?

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

Question 42

In vertebrates, what does the CNS consist of?

A)the brain and grey matter
B)the brain and the spinal cord
C)the brain and reflexes
D)the spinal cord and grey matter

Question 43

What will be caused in the postsynaptic membrane by the binding of a neurotransmitter to ligand-gated Na⁺ channels?

A)hyperpolarization
B)depolarization
C)repolarization
D)apolarization

Question 44

Which of the following is a possible result of EPSP and IPSP activity?

A)an unusually strong action potential forms
B)an unusually strong presynaptic potential forms
C)temporal summation in a postsynaptic neuron
D)temporal summation in a presynaptic neuron

Question 45

Which of the following involves Na⁺?

A)resting membrane potential
B)repolarization
C)hyperpolarization
D)depolarization

Question 46

What will a hollow neural tube develop into?

A)spinal nerves
B)the brain
C)motor nerves
D)the forebrain, midbrain, and hindbrain

Question 47

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?

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

Question 48

Which of the following refers to a graded, subthreshold change in the postsynaptic membrane potential that moves toward threshold?

A)depolarization
B)IPSP
C)hyperpolarization
D)EPSP

Question 49

What can the neurotransmitter acetylcholine in vertebrates do?

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 50

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

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

Question 51

Which of the following is common to all vertebrates?

A)a small brain
B)large ganglia
C)a midbrain
D)a convoluted cerebrum

Question 52

What type of neuron directly stimulates a muscle or gland?

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

Question 53

What can neuropeptide neurotransmitters do?

A)act as pain reducers and initiate euphoria
B)act as a postsynaptic membrane inhibitor
C)act as a direct neurotransmitter between neurons and muscle cells
D)directly open K⁺ channels to inhibit neurons

Question 54

Which of the following animals has the most-advanced cephalization?

A)an arthropod
B)an echinoderm
C)a flatworm
D)a chordate

Question 55

What will be caused in the postsynaptic membrane by the binding of a neurotransmitter to ligand-gated K⁺ channels?

A)apolarization
B)depolarization
C)repolarization
D)hyperpolarization

Question 56

Which of the following animals has the least-advanced nerve cord?

A)human
B)flatworm
C)arthropod
D)octopus

Question 57

What is cephalization in animals most associated with?

A)bilateral symmetry
B)ganglia
C)nerves
D)nerve nets

Question 58

How is sensory information transmitted to the CNS?

A)by the efferent neurons of the autonomic nervous system
B)by the somatic neurons of the peripheral nervous system
C)by the somatic neurons of the sympathetic division
D)by the afferent neurons of the peripheral nervous system

Question 59

In animals with a brain, what are the two major divisions of the nervous system?

A)cranial and spinal nerves
B)central and peripheral nervous systems
C)nerves from the brain and the peripheral systems
D)autonomic and peripheral systems

Question 60

What will be caused in the postsynaptic membrane by the binding of a neurotransmitter to ligand-gated Cl- channels?

A)depolarization
B)repolarization
C)hyperpolarization
D)apolarization

Question 61

Distinguish between the central and peripheral nervous systems.

Question 62

Action potentials may vary in magnitude along a particular excitable membrane.

Question 63

Match each term with its definition.
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
reflexes

Question 64

Explain how neuron action potential propagation rate can be increased.

Question 65

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?

Question 66

The parasympathetic division predominates in situations involving stress.

Question 67

The nervous systems of arthropods are composed of nerve nets.

Question 68

Direct neurotransmitters bind to G protein-coupled receptors.

Question 69

Which sentence presents characteristics of sympathetic and parasympathetic systems, respectively?

A)The sympathetic system controls external stimuli, while the parasympathetic system controls internal stimuli.
B)The sympathetic system generally predominates during physical activity, while the parasympathetic system predominates during nonphysical activity.
C)The sympathetic system and the parasympathetic systems both release norepinephrine.
D)The sympathetic system is under voluntary control, and the parasympathetic system is under involuntary control.

Question 70

In terms of changes in membrane potential, compare and contrast action potentials and graded potentials.

Question 71

Oligodendrocytes are responsible for myelinating central nervous system axons.

Question 72

Neurotransmitters are stored in vesicles located within axon terminals.

Question 73

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

Question 74

Saltatory conduction is the slowest form of action potential propagation.

Question 75

Cephalization is associated with bilateral symmetry.

Question 76

Valium is a drug that causes voltage-gated Cl- channels to open. What effects would this cause in a postsynaptic membrane?

Question 77

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

Question 78

The additive effect of one neuron sending many EPSPs to another neuron over a brief period of time is called spatial summation.

Question 79

EPSPs can form due to the diffusion of Na⁺ across a neuron plasma membrane.

Question 80

Which of the following is a characteristic of the autonomic nervous system?

A)It is a functional division of the central nervous system.
B)It controls body movements that are under unconscious control.
C)It is composed of parasympathetic and sympathetic divisions.
D)It includes both afferent and efferent nerve fibres.