Nervous System Part I Flashcards
Cluster of peripherally located nerve cell bodies
Ganglion
Which root of the axons near the spinal chord have the ganglion?
Dorsal root
Location of nerve cell bodies for axons bringing sensory info into the spinal cord (CNS)
Dorsal root ganglion
There is no ganglion in the _______ root
Ventral root
Which root does the sensory input travel through?
Dorsal
Which root does the motor/autonomic output travel through?
Ventral
Spinal nerves divide to form dorsal/ventral primary ______
Rami
Another name for sensory input axons
Afferent axons
Type of axons in which nerve impulses flow towards the CNS
Afferent axons
Which root do afferent axons make up?
Dorsal root
Which root does efferent axons make up?
Ventral root
Nerve impulses that flow away from the CNS
Efferent
Motor or autonomic axons are ______ axons
efferent axons
What’s the difference between the somatic nervous system and the autonomic nervous system?
Somatic - conscious motor control
Autonomic - unconscious motor control (organs)
What would be the official name of the nerve fibers running motor control to your skeletal muscles?
Somatic efferent fibers (axons)
Which nerves are heavily myelinated? (somatic or autonomic)
Somatic
Does a heavier myelin sheath mean faster conduction or slower?
Faster
Which motor fiber system has a preganglionic/postganglionic schema?
Autonomic system
Which system supplies motor to the viscera?
Autonomic system
What does viscera mean?
smooth/cardiac muscle
“rest and digest” system
Parasympathetic nervous system
“fight or flight” system
Sympathetic nervous system
Preganglionic axons originate from the _______
nucleus
Is the nucleus in the CNS or PNS?
CNS
Were do postganglionic axons originate from?
Ganglions
What’s between the preganglionic axon and the ganglion
synapse
Which has a longer preganglionic axon? (sympathetic or parasympathetic)
Parasympathetic
Responsible for the integration of the nervous system
CNS
What kind of neurons make up the sensory ganglia and fibers?
Unipolar neurons
What kind of neurons carry special sensation to the CNS?
Bipolar neurons
Type of neuron that makes up motor fibers and internuncials
Multipolar neurons
In non-excitable tissue, does resting Vm change?
NO
Most common cholinergic neurotransmitter?
Acetylcholine
Most common adrenergic neurotransmitter?
Norepi
Main inhibitory neurotransmitter
GABA
When several presynaptic axons come together to 1 postsynaptic neuron
Convergence
When 1 presynaptic axon connects to 2 postsynaptic neurons
Divergence
Synapse between presynaptic axon and dendrites on postsynaptic neuron
Axonodendritic synapse
Synapse between presynaptic axon and soma of the postsynaptic neuron
Axonosomatic synapse
Synapse between presynaptic axon and axon of the postsynaptic neuron
Axonoaxonic synapse
Depolarized region of an axon that is myelinated
Node of Ranvier
What type of conduction when impulse skipps across the nodes of ranvier down an axon?
Saltatory conduction
Type of cells that provide myelin to neurons in the PNS
Schwann cells
What type of glial cell provides myelin to the CNS?
Oligodendrocytes
Name the 4 types of glial cells in the CNS
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
Non-neuronal cells within the CNS
Glial cells
Do glial cells carry nerve impulses?
No
What 2 types of glial cells digest parts of dead neurons (similar to WBCs)
Astrocytes
Microglia
These types of glial cells are star shaped and hold neurons in place and help form the blood brain barrier via perivascular feet (kinda looks like axon somas smashed against the external vasculature walls)
Astrocytes
Which type of astrocyte helps form the blood brain barrier and is found in white matter?
fibrous astrocytes
Which type of astrocyte is found in gray matter?
Protoplasmic astrocytes
What type of glial cell lines the cavities or ventricles of the CNS
Ependymal cells
What does rostral mean
Towards the front
What does cephalic mean
toward the head
What does caudal mean
toward the tail
What does ipsilateral mean
same side
What does contralateral mean
opposite side
Name the 3 primary pre-natal brain vesicles from top to bottom
Prosencephalon
Mesencephalon
Rhombencephalon
What secondary pre-natal brain vesicles does the prosencephalon turn into?
Telencephalon
Diencephalon
What secondary pre-natal brain vesicle does the mesencephalon turn into?
Mesencephalon (stays the same!)
What secondary pre-natal brain vesicles does the rhombencephalon turn into?
Metencephalon
Myelencephalon
What part of the brain does the telencephalon turn into? (think top to bottom)
Cerebrum
What part of the brain does the diencephalon turn into?
Thalamus
Hypothalamus
What part of the brain does the mesencephalon turn into?
Midbrain
What part of the brain does the metencephalon turn into?
Cerebellum
Pons
What part of the brain does the Myelenchephalon turn into?
Medulla
This part of the midbrain receives visual input that initiates a behavioral response (ex. startle response)
It is the 2 superior bumps from the posterior view
Superior Colliculi
This part of the midbrain controls auditory regulation of sound
It is the 2 inferior bumps from the posterior view
Inferior colliculi
Fibers that carry information to and from the brainstem and cerebellum (3 sets)
Cerebellar peduncles
Superior
Middle
Inferior
What makes up the upper portion of the 4th ventricle?
Pons
What makes up the lower portion of the 4th ventricle?
Medulla
What part of the brainstem is the facial n. fairly superficial?
Facial colliculus
Bilateral inferior bumps just medial to the cerebellar peduncles
Facial colliculi
Bilateral superior bumps just medial to the cerebellar peduncles
Medial eminence
Dorsal columns carry tactile info upward to the _________
Thalamus
Which dorsal column connects to the lower extremity pathway?
Gracile tubercules
Which dorsal column connects to the upper extremity pathway?
Cuneate tubercules
The official name for the medial dorsal columns of the brainstem
Gracile tubercules
The official name for the lateral dorsal columns of the brainstem
Cuneate tubercules
Triangle area that makes up the floor of the 4th ventricle
Rhomboid fossa
The striae medullaries are fibers of which CN?
CN VIII (vestibulocochlear n.)
The most inferior point within the 4th ventricle. Makes the inferior tip of the rhomboid fossa
Obex
Vomiting center (located within the 4th ventricle, and can see it with posterior view of rhomboid fossa)
Area Postrema
The cerebral peduncles are fiber of the ________ motor system
corticospinal
What is the start and end point of corticospinal fibers?
Cortico - start in cerebral cortex
spinal - end in spinal chord
Where do the majority of fibers decussate in the corticospinal motor pathway?
Pryramids on the medulla
What does decussate mean?
cross
Where do the rest of the fibers decussate if they didn’t at the pyramids of the medulla?
Cervical spinal chord
The name of structures similar to gyri on cerebellum
Folia
Separates the lobes of the cerebellum medially
Vermis
Bilateral structures on the posterior lobes of the cerebellum
Cerebellar tonsils
Cerebellum provides _________ motor control
ipsilateral
The cerebral cortex provides __________ motor control
contralateral
What does the vermis control? (think about pathways)
Equilibrium and balance
*it gets impulses from vestibule
Cerebellar lesion = what 3 things
Ataxia (unsteady, random movements)
Dysynergia (abrupt movement during voluntary movement)
Dysmetria (finger to nose/heel to shin can’t do it)
What part of the brainstem reticular formation regulates awareness level?
Ascending portion
This part of the brainstem reticular formation receives sensory/activity input and uses it to regulate LOC
Ascending portion
ADHD results in dysfunction with what part of the brainstem reticular formation?
Ascending portion
*fails to filter out “noise” from sensory input
The reticular activating system (RAS) is part of the ________ portion of the brainstem reticular formation?
Ascending portion
Which portion of the brainstem reticular formation regulates muscle tone & is affected by LOC?
Descending portion
Hypertonia
Increased muscle tone
*regulated by descending portion of brainstem reticular formation
Hypotonia
Decreased muscle tone
*regulated by descending portion of brainstem reticular formation
What part of the CNS controls muscles involved in breathing?
Medulla
What part of the CNS controls rate of breathing?
Pons
What parts of the CNS contain the respiratory centers?
Medulla
Pons
