1 | Page
APHY 164 Final Questions and Correct
Answers
what are the 3 essential roles of the nervous system Ans: 1.
sensing
2. integrating
3. responding
what are the 5 types of glial cells Ans: 1. oligodendrocytes (myelin
sheath)
2. ependymal cells (line spinal cord)
3. microglia (phagocytosis)
4. astrocytes (blood-brain barrier, nourish neurons)
5. schwann cells (myelin sheath around nerves in PNS)
what are the 3 classes of neurons Ans: 1. sensory (afferent)
2. motor (efferent)
3. interneurons (only CNS, connect motor and sensory)
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, 2 | Page
- multipolar (1 axon multiple dendrites, bipolar (2 processes) and
unipolar (1 process)
what makes up the structure of a neuron Ans: Soma- cell body,
contains nucleus
Dendrites- recieve signals
Axon- carries signals away
Myelin Sheath- encases axon, lipid
Nodes of Ranvier- gaps in myelin sheath
Synaptic Knob- end of axon branches (contain nuerotransmitter)
what are the 5 stages of impulse conduction Ans: 1. resting
potential- inside - , outside +
2. depolarization- stimulus makes Na enter cells
3. Action Potential- adjacent areas open, more Na enters
4. repolarization- K flows out
5. refractory period- membrane polarized, Na and K are switched,
NaK pumps restore order
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, 3 | Page
- in myelinated fibers AP's occur in nodes of ranvier (saltatory
conduction)
what structures make up the spinal cord Ans: Gray Matter- mostly
motor/interneurons, contains posterior (dorsal) and ventral
(anterior) horns
- posterior (sensory/into), anterior (motor/away)
White Matter- bundles of axons, myelinated
epidural space and central canal
Meninges- Pia Mater (inner), Arachnoid (mid), and Dura Mater
(tough/outer) are fibrous connective tissue protecting spinal cord
what are the 2 spinal nerve tracts Ans: 1. Ascending- sensory
signals up spinal cord to brain (dorsal column, spinocerebellar
tract, spinothalamic tract)
© 2025 All rights reserved
APHY 164 Final Questions and Correct
Answers
what are the 3 essential roles of the nervous system Ans: 1.
sensing
2. integrating
3. responding
what are the 5 types of glial cells Ans: 1. oligodendrocytes (myelin
sheath)
2. ependymal cells (line spinal cord)
3. microglia (phagocytosis)
4. astrocytes (blood-brain barrier, nourish neurons)
5. schwann cells (myelin sheath around nerves in PNS)
what are the 3 classes of neurons Ans: 1. sensory (afferent)
2. motor (efferent)
3. interneurons (only CNS, connect motor and sensory)
© 2025 All rights reserved
, 2 | Page
- multipolar (1 axon multiple dendrites, bipolar (2 processes) and
unipolar (1 process)
what makes up the structure of a neuron Ans: Soma- cell body,
contains nucleus
Dendrites- recieve signals
Axon- carries signals away
Myelin Sheath- encases axon, lipid
Nodes of Ranvier- gaps in myelin sheath
Synaptic Knob- end of axon branches (contain nuerotransmitter)
what are the 5 stages of impulse conduction Ans: 1. resting
potential- inside - , outside +
2. depolarization- stimulus makes Na enter cells
3. Action Potential- adjacent areas open, more Na enters
4. repolarization- K flows out
5. refractory period- membrane polarized, Na and K are switched,
NaK pumps restore order
© 2025 All rights reserved
, 3 | Page
- in myelinated fibers AP's occur in nodes of ranvier (saltatory
conduction)
what structures make up the spinal cord Ans: Gray Matter- mostly
motor/interneurons, contains posterior (dorsal) and ventral
(anterior) horns
- posterior (sensory/into), anterior (motor/away)
White Matter- bundles of axons, myelinated
epidural space and central canal
Meninges- Pia Mater (inner), Arachnoid (mid), and Dura Mater
(tough/outer) are fibrous connective tissue protecting spinal cord
what are the 2 spinal nerve tracts Ans: 1. Ascending- sensory
signals up spinal cord to brain (dorsal column, spinocerebellar
tract, spinothalamic tract)
© 2025 All rights reserved
