HCR 240 LESSON 4: THE NEUROLOGICAL SYSTEM PART 1 2026/2027 |
STUDY GUIDE, PRACTICE QUESTIONS, ANSWERS & EXAM REVIEW
Central Nervous System (CNS) - ANS ✔✔consists of the brain and spinal cord
peripheral nervous system (PNS) - ANS ✔✔is composed of cranial nerves and the spinal nerves and their
gladii
differentiated into afferent pathways (ascending pathways) and efferent pathways (descending
pathways)
consists of the somatic nervous system and the autonomic nervous system (ANS)
afferent pathway - ANS ✔✔carry sensory information towards the CNS
efferent pathways - ANS ✔✔innervate skeletal muscle or effector organs by transmitting motor impulses
away from the CNS
Somatic nervous system - ANS ✔✔consists of pathways that regulate voluntary motor control (e.g.
skeletal muscle)
autonomic nervous system (ANS) - ANS ✔✔involved with regulation of the body's internal environment
(viscera) through involuntary control of organ systems
further divides into the sympathetic and parasympathetic divisions.
effector organs - ANS ✔✔organs that are innervated by a specific components of the nervous system
neuron - ANS ✔✔primary cell of the nervous system
neuroglial cells - ANS ✔✔CNS:
- astrocytes
- microglial cells
- oligodendrocytes
PNS:
- satellite cells
- Schwann (neurilemma)
provide structural support, protection and nutrition for the neurons.
Microtubules - ANS ✔✔transport substances within the neuron
neurofibrils - ANS ✔✔very thin supportive fibers that extend throughout the neuron
microfilaments - ANS ✔✔thought to be involved in transport of cellular products within the neuron
,nissal substance - ANS ✔✔endoplasmic reticulum and ribosomes involved in protein synthesis within the
neuron
Neuron has 3 parts - ANS ✔✔cell body
dendrites
axon
Cell body of neuron - ANS ✔✔soma
dendrites of neuron - ANS ✔✔are the main receiving region of a neuron
extensions that carry nerve impulses towards the cell
axon of neurons - ANS ✔✔long, conductive projections that carry nerve impulses away from the body
ganglia and plexuses - ANS ✔✔groups of cell bodies in the PNS
axon hillock - ANS ✔✔cone shaped process where the axon leaves the cell body
myelin - ANS ✔✔A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly
greater transmission speed of neural impulses as the impulse hops from one node to the next.
myelin sheath - ANS ✔✔membrane surrounding the axon
Nodes of Ranvier - ANS ✔✔gaps in the myelin sheath
saltatory conduction - ANS ✔✔the jumping of action potentials from node to node
caused by the myelin sheath
demyelination diseases - ANS ✔✔disorders of the myelin sheath
ex:
multiple sclerosis
Guillain-Barre syndrome
unipolar neurons - ANS ✔✔have one process that branches shortly after leaving the cell body
ex: Retina
pseudounipolar neurons - ANS ✔✔have one process
the dendritic portion of of each of these neurons extends away from the CNS and the axon portion
projects into the CNS
ex:
sensory neurons in both cranial and spinal nerves
, Bipolar neurons - ANS ✔✔have two distinct processes arising from the cell body.
ex:
Rod and cone cells within the retina
Multipolar neuron - ANS ✔✔the most common neuron
have multiple processes capable of extensive branching.
Ex: Motor neurons
Sensory neurons - ANS ✔✔carry impulses from the peripheral sensory receptors to the CNS
Associational neurons (interneurons) - ANS ✔✔transmit impulses from neuron to neuron
aka Sensory to Motor neurons.
located w/n the CNS only.
Motor neurons - ANS ✔✔transmit impulses away from the CNS to an effector (i.e., skeletal muscle or
organs).
neuromuscular (myoneural) junction - ANS ✔✔area where a neuron's (nerve cell) axon interacts with
muscle cell
Neuroglia - ANS ✔✔the general classification of nonneuronal cells that support the neurons of the CNS
Astrocytes - ANS ✔✔Provide structural and metabolic support for neurons.
surround blood vessels, fill the spaces between neurons and contribute to synaptic function in the CNS
Oligodendrocytes - ANS ✔✔form myelin sheath w/n the CNS
Epdendymal Cells - ANS ✔✔line the cerebrospinal fluid (CSF) filled cavitites of the CNS
microglia - ANS ✔✔removes cell debris (phagocytosis) in the CNS
Schwann cells - ANS ✔✔form myelin sheath in PNS
direct axon regrowth and functional recovery in the PNS
Nonmyelinating Schwann Cells - ANS ✔✔provide metabolic support
Wallerian degeneration - ANS ✔✔occurs in the axon distal when an axon is severed
characteristic swelling appearing within the portion of the axon distal to the cut
STUDY GUIDE, PRACTICE QUESTIONS, ANSWERS & EXAM REVIEW
Central Nervous System (CNS) - ANS ✔✔consists of the brain and spinal cord
peripheral nervous system (PNS) - ANS ✔✔is composed of cranial nerves and the spinal nerves and their
gladii
differentiated into afferent pathways (ascending pathways) and efferent pathways (descending
pathways)
consists of the somatic nervous system and the autonomic nervous system (ANS)
afferent pathway - ANS ✔✔carry sensory information towards the CNS
efferent pathways - ANS ✔✔innervate skeletal muscle or effector organs by transmitting motor impulses
away from the CNS
Somatic nervous system - ANS ✔✔consists of pathways that regulate voluntary motor control (e.g.
skeletal muscle)
autonomic nervous system (ANS) - ANS ✔✔involved with regulation of the body's internal environment
(viscera) through involuntary control of organ systems
further divides into the sympathetic and parasympathetic divisions.
effector organs - ANS ✔✔organs that are innervated by a specific components of the nervous system
neuron - ANS ✔✔primary cell of the nervous system
neuroglial cells - ANS ✔✔CNS:
- astrocytes
- microglial cells
- oligodendrocytes
PNS:
- satellite cells
- Schwann (neurilemma)
provide structural support, protection and nutrition for the neurons.
Microtubules - ANS ✔✔transport substances within the neuron
neurofibrils - ANS ✔✔very thin supportive fibers that extend throughout the neuron
microfilaments - ANS ✔✔thought to be involved in transport of cellular products within the neuron
,nissal substance - ANS ✔✔endoplasmic reticulum and ribosomes involved in protein synthesis within the
neuron
Neuron has 3 parts - ANS ✔✔cell body
dendrites
axon
Cell body of neuron - ANS ✔✔soma
dendrites of neuron - ANS ✔✔are the main receiving region of a neuron
extensions that carry nerve impulses towards the cell
axon of neurons - ANS ✔✔long, conductive projections that carry nerve impulses away from the body
ganglia and plexuses - ANS ✔✔groups of cell bodies in the PNS
axon hillock - ANS ✔✔cone shaped process where the axon leaves the cell body
myelin - ANS ✔✔A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly
greater transmission speed of neural impulses as the impulse hops from one node to the next.
myelin sheath - ANS ✔✔membrane surrounding the axon
Nodes of Ranvier - ANS ✔✔gaps in the myelin sheath
saltatory conduction - ANS ✔✔the jumping of action potentials from node to node
caused by the myelin sheath
demyelination diseases - ANS ✔✔disorders of the myelin sheath
ex:
multiple sclerosis
Guillain-Barre syndrome
unipolar neurons - ANS ✔✔have one process that branches shortly after leaving the cell body
ex: Retina
pseudounipolar neurons - ANS ✔✔have one process
the dendritic portion of of each of these neurons extends away from the CNS and the axon portion
projects into the CNS
ex:
sensory neurons in both cranial and spinal nerves
, Bipolar neurons - ANS ✔✔have two distinct processes arising from the cell body.
ex:
Rod and cone cells within the retina
Multipolar neuron - ANS ✔✔the most common neuron
have multiple processes capable of extensive branching.
Ex: Motor neurons
Sensory neurons - ANS ✔✔carry impulses from the peripheral sensory receptors to the CNS
Associational neurons (interneurons) - ANS ✔✔transmit impulses from neuron to neuron
aka Sensory to Motor neurons.
located w/n the CNS only.
Motor neurons - ANS ✔✔transmit impulses away from the CNS to an effector (i.e., skeletal muscle or
organs).
neuromuscular (myoneural) junction - ANS ✔✔area where a neuron's (nerve cell) axon interacts with
muscle cell
Neuroglia - ANS ✔✔the general classification of nonneuronal cells that support the neurons of the CNS
Astrocytes - ANS ✔✔Provide structural and metabolic support for neurons.
surround blood vessels, fill the spaces between neurons and contribute to synaptic function in the CNS
Oligodendrocytes - ANS ✔✔form myelin sheath w/n the CNS
Epdendymal Cells - ANS ✔✔line the cerebrospinal fluid (CSF) filled cavitites of the CNS
microglia - ANS ✔✔removes cell debris (phagocytosis) in the CNS
Schwann cells - ANS ✔✔form myelin sheath in PNS
direct axon regrowth and functional recovery in the PNS
Nonmyelinating Schwann Cells - ANS ✔✔provide metabolic support
Wallerian degeneration - ANS ✔✔occurs in the axon distal when an axon is severed
characteristic swelling appearing within the portion of the axon distal to the cut
