EXSS 380 EXAM 1QUESTIONS AND ANSWERS
What is the definition of a neuron? - answers :functional unit of the nervous system
What role do dendrites play in the neuron? - answers :receive messages from other
cells
What role does the soma (cell body) play in the neuron? - answers :the cell's life support
center
What role does the axon play in the neuron? - answers :passes messages away from
soma to other neurons, muscles and glands
Where do action potentials fire to propagate down the axon? - answers :nodes of
ranvier
What muscle neurotransmitter do we focus on? - answers :acetylcholine (ach)
What types of channels are very dense at nodes of ranvier? - answers :sodium
channels
What happens when the synaptic end bulbs of one neuron synapse with the dendrites
of another? - answers :ach is released into synaptic gap which allows the synapsed cell
to open and receive the neurotransmitter
What type of neurons are afferent? - answers :sensory
What type of neurons are efferent? - answers :motor
About 90% of all neurons are ________ - answers :interneurons
What is the most direct path of physiological electrochemical signaling in a neuron -
answers :dendrite, soma, axon hillock, axon, synaptic vesicles
Sensory receptors transmit action potentials on an afferent nerve. What structure would
the action potential reach first? - answers :dorsal root ganglion
Resting membrane potential is typically around _______. During depolarization, the cell
reaches a charge of about ________. - answers :-70mv, 30mv
Action potentials typically do not backfire when propagating on an axon because -
answers :the sodium potassium pump moves ions across the cell membrane against
gradients; the nerve immediately behind the leading edge of the action potential is still
positively charged and therefore cannot propagate an action potential in the other
direction; large amounts of k+ channels on the membrane of the neuron which leak k+
into the neuron
,When a postsynaptic cell receives more ipsp's than epsp's from a presynaptic neuron it
is connected to, what is most likely going to occur to that cell? - answers :hyper
polarization
Which factors are involved in maintaining appropriate resting membrane potential? -
answers :the sodium potassium pump moving ions back across the membrane, non-
gated leaky k+ and na+ channels allow ions to pass through the cell; the concentration
gradient attracting k+ out of the cell and na+ into the cell
Acetylcholine is a neurotransmitter that is primarily associated with what effect? -
answers :depolarization of skeletal muscles
Muscles that are responsible for fine movements and allow for precise control have
______ muscle fibers per alpha motor neuron - answers :fewer
An area of heavy myelination is often called ________ matter, and action potentials
move _______ across those neural tracks. - answers :white: quickly
The na+/k+ pump mechanism works against the concentration gradient to pump
_______ na+ _________ the nerve cell, and ______ k+ _______ the cell. - answers :3;
out; 2; in
Which structure specifically facilitates the speed of propagation of action potentials -
answers :schwann cells
Automatic processes such as increasing heart rate and quickening rate of breathing are
controlled by the - answers :autonomic nervous system, sympathetic nervous system
The majority of neurons within the nervous system are alpha motor neurons - answers
:false
Depolarization of an inhibitory interneuron will cause an epsp on the post synaptic
neuron - answers :false
There are more neurons in the nervous system than glial cells - answers :false
What is the difference between a nerve and a tract? - answers :a nerve is a bundle of
fibers in the pns, a tract is a bundle of fibers in the cns (spinal column)
What is the difference between a nucleus and a ganglion? - answers :a nucleus is a
cluster of nerve cell bodies in the cns, a ganglion is a cluster of nerve cell bodies in the
pns
What are the 4 steps of transmission of neuron information? - answers
:neurotransmitters alter status of post-synaptic membrane (excitatory or inhibitory),
, soma generates action potential ("on" signal), action potential travels down axon, action
potential causes release of neurotransmitters
In order to propagate an action potential, the inside of the cell must be more _______
than the outside of the cell - answers :positive
Excitation and inhibition are caused by changes in _______ _______ _______ -
answers :resting membrane potential
What is an epsp and what occurs as a result? - answers :excitatory post synaptic
potential, na+ influx causing depolarization (cell becomes less negative)
What is an ipsp and what occurs as a result? - answers :inhibitory post synaptic
potential, k+ exodus causing hyperpolarization (cell becomes more negative)
What is the all-or-none phenomenon of action potentials? - answers :once threshold is
crossed, it doesn't matter how large the stimulus is because action potentials fire
completely or not at all
How the neuromuscular system initiates and coordinates muscle activity to produce
movement refers to: - answers :muscle control
Movement of muscles can be modulated by sensory information provided by what
system? - answers :peripheral nervous system
The acquisition of motor skills refers to: - answers :motor learning
An activity that requires voluntary movement to achieve a goal refers to: - answers
:motor skill
What are the three functions of the nervous system? - answers :sensory
Integrative
Motor
The ______is superior to the foramen magnum, while the _____is inferior to the
foramen magnum - answers :brain
Spinal cord
What are the two divisions of the peripheral nervous system? - answers :autonomic
nervous system
Somatic nervous system
In what division of the pns, can motor stimuli be either excitatory or inhibitory? - answers
:autonomic nervous system
What is the definition of a neuron? - answers :functional unit of the nervous system
What role do dendrites play in the neuron? - answers :receive messages from other
cells
What role does the soma (cell body) play in the neuron? - answers :the cell's life support
center
What role does the axon play in the neuron? - answers :passes messages away from
soma to other neurons, muscles and glands
Where do action potentials fire to propagate down the axon? - answers :nodes of
ranvier
What muscle neurotransmitter do we focus on? - answers :acetylcholine (ach)
What types of channels are very dense at nodes of ranvier? - answers :sodium
channels
What happens when the synaptic end bulbs of one neuron synapse with the dendrites
of another? - answers :ach is released into synaptic gap which allows the synapsed cell
to open and receive the neurotransmitter
What type of neurons are afferent? - answers :sensory
What type of neurons are efferent? - answers :motor
About 90% of all neurons are ________ - answers :interneurons
What is the most direct path of physiological electrochemical signaling in a neuron -
answers :dendrite, soma, axon hillock, axon, synaptic vesicles
Sensory receptors transmit action potentials on an afferent nerve. What structure would
the action potential reach first? - answers :dorsal root ganglion
Resting membrane potential is typically around _______. During depolarization, the cell
reaches a charge of about ________. - answers :-70mv, 30mv
Action potentials typically do not backfire when propagating on an axon because -
answers :the sodium potassium pump moves ions across the cell membrane against
gradients; the nerve immediately behind the leading edge of the action potential is still
positively charged and therefore cannot propagate an action potential in the other
direction; large amounts of k+ channels on the membrane of the neuron which leak k+
into the neuron
,When a postsynaptic cell receives more ipsp's than epsp's from a presynaptic neuron it
is connected to, what is most likely going to occur to that cell? - answers :hyper
polarization
Which factors are involved in maintaining appropriate resting membrane potential? -
answers :the sodium potassium pump moving ions back across the membrane, non-
gated leaky k+ and na+ channels allow ions to pass through the cell; the concentration
gradient attracting k+ out of the cell and na+ into the cell
Acetylcholine is a neurotransmitter that is primarily associated with what effect? -
answers :depolarization of skeletal muscles
Muscles that are responsible for fine movements and allow for precise control have
______ muscle fibers per alpha motor neuron - answers :fewer
An area of heavy myelination is often called ________ matter, and action potentials
move _______ across those neural tracks. - answers :white: quickly
The na+/k+ pump mechanism works against the concentration gradient to pump
_______ na+ _________ the nerve cell, and ______ k+ _______ the cell. - answers :3;
out; 2; in
Which structure specifically facilitates the speed of propagation of action potentials -
answers :schwann cells
Automatic processes such as increasing heart rate and quickening rate of breathing are
controlled by the - answers :autonomic nervous system, sympathetic nervous system
The majority of neurons within the nervous system are alpha motor neurons - answers
:false
Depolarization of an inhibitory interneuron will cause an epsp on the post synaptic
neuron - answers :false
There are more neurons in the nervous system than glial cells - answers :false
What is the difference between a nerve and a tract? - answers :a nerve is a bundle of
fibers in the pns, a tract is a bundle of fibers in the cns (spinal column)
What is the difference between a nucleus and a ganglion? - answers :a nucleus is a
cluster of nerve cell bodies in the cns, a ganglion is a cluster of nerve cell bodies in the
pns
What are the 4 steps of transmission of neuron information? - answers
:neurotransmitters alter status of post-synaptic membrane (excitatory or inhibitory),
, soma generates action potential ("on" signal), action potential travels down axon, action
potential causes release of neurotransmitters
In order to propagate an action potential, the inside of the cell must be more _______
than the outside of the cell - answers :positive
Excitation and inhibition are caused by changes in _______ _______ _______ -
answers :resting membrane potential
What is an epsp and what occurs as a result? - answers :excitatory post synaptic
potential, na+ influx causing depolarization (cell becomes less negative)
What is an ipsp and what occurs as a result? - answers :inhibitory post synaptic
potential, k+ exodus causing hyperpolarization (cell becomes more negative)
What is the all-or-none phenomenon of action potentials? - answers :once threshold is
crossed, it doesn't matter how large the stimulus is because action potentials fire
completely or not at all
How the neuromuscular system initiates and coordinates muscle activity to produce
movement refers to: - answers :muscle control
Movement of muscles can be modulated by sensory information provided by what
system? - answers :peripheral nervous system
The acquisition of motor skills refers to: - answers :motor learning
An activity that requires voluntary movement to achieve a goal refers to: - answers
:motor skill
What are the three functions of the nervous system? - answers :sensory
Integrative
Motor
The ______is superior to the foramen magnum, while the _____is inferior to the
foramen magnum - answers :brain
Spinal cord
What are the two divisions of the peripheral nervous system? - answers :autonomic
nervous system
Somatic nervous system
In what division of the pns, can motor stimuli be either excitatory or inhibitory? - answers
:autonomic nervous system
