Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Boards: Neurology + Ophthalmology > Neuro Physiology > Flashcards

Neuro Physiology Flashcards

(48 cards)

Start Studying
1
Q

What are the functions of glial cells? (5)

A
  • produce myelin sheets
  • modulate growth of damaged or developing neurons
  • buffer extracellular neurotransmitter and K+ concentrations
  • forms contacts between neurons
  • immune responses of the nervous system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where do afferent sensory versus efferent motor axons exit or enter the spinal cord?

A

afferent sensory - enter through the dorsal roots

efferent motor - exit through the ventral roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What part of the brain does the hypothalamus belong to?

A

Diencephalon - forebrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Name these structures

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 3 protective layers of the CNS?

A
  • Pia mater - single layer fibroblasts
  • Arachnoid - spiderweb appearance, thin layer fibroblasts (subarachnoid space with CNS between pia mater and arachnoid
  • Dura mater - thick layer fibroblasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is axoplasmic transport?

A

transport of proteins/macromolecules produced in the neuron cell body and carried through the axon to the presynaptic terminals

needed transprot because axons are not able to produce proteins themselves / lack ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are PNS versus CNS glial cells called?

A
  • PNS Swann cells
  • CNS Oligodendrocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the indentation between myelin sheets called?

A

nodes of Ranvier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the normal resting membrane potentia of neurons?

A

-70 mV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the differences between postsynaptic Na+ versus K+ channel opening

A

If neurotransmitter opens Na+ channels&raquo_space; moves membrane potential towards more positive&raquo_space; triggering depolarization = excitatory postsynaptic potential

If neurotransmitter open K+ channel&raquo_space; moves membrane potential more towards hyperpolarzied (i.e., more negative)&raquo_space; inhibitory postsynaptic potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is destroyed in Coonhound paralysis?

A

myelin sheets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Besides surgery list 4 treatment options for insulinomas

A
  • glucocorticoids - increases gluconeogenesis
  • diazoxide - inhibits insulin secretion
  • somatostatin - increases gluconeogenesis
  • streptozocin - toxic to beta cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What trigger release of presynaptic vesicles?

A

increase in IC Ca++

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is synaptobrevin and syntaxin/SNAP-25?

A

binding proteins at the presynaptic membrane that bind and align acetylcholine filled vesicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does Ca++ bind to to cause vesicle release at the presynaptic membrane?

A

synaptotagmin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What receptors does acetylcholine bind to at the postsynaptic membrane in neuromuscular junctions?

A

nicotinic acetylcholine receptors

when bound - channel opens - Na+ diffuses into the cell&raquo_space; depolarizaiton&raquo_space; excitatory nerve impulse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

List examples for these major neurotransmitter classes:

  • amino acids
  • amines
  • catecholamines
  • peptides
  • opioids
  • purines
  • gases
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does tetanus excert its effects?

A

tetanospasmin - blocks synaptic release of GABA and glycine by cleaving synaptobrevin (vesicle binding protein)

i.e., blocks release of inhibitory neurotransmitters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are intrafusal versus extrafusal muscle fibers innervated by?

A

extrafusal - alpha motor neurons
intrafusal - gamma motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What neurons typically malfunction to cause LMN signs. Where are these neurons located and what do they innervate?

Study These Flashcards
A

alpha motor neurons

cell bodies + dendrites located in the CNS (ventral horn spinal cord or brainstem if CN)

axons innervate the extrafusal skeletal muscle fibers

21
Q

What are the 4 hallmarks of LMN signs?

Study These Flashcards
A
  • paralysis or paresis - flaccid
  • loss of reflex arch - loss of segmental and intersegmental reflexes
  • muscle atrophy - within days of the injury
  • changes on electromyography within a few days
22
Q

where are upper motor neurons located?

Study These Flashcards
A

completely in the CNS&raquo_space; influence the lower motro neurons&raquo_space; send axons down the spinal cord or into the brain stem to control LMNs

23
Q

What are the hallmarks of UMN injuries/disease?

Study These Flashcards
A
  • inappropriate or abnormal movement (spinal cord injury often causes weakness, brain orignin rigidity, circling, seizures, inappropriate movements)
  • no muscle atrophy - LMN still intact
  • retained but exaggerated segmental reflexes - loss of UMN inhibitory control
  • normal electromyogram
24
Q

Where does the motor neuron unit exit the spinal cord?

Study These Flashcards
A

ventral horn of spinal cord gray matter

25
With LR and LH weakness and proprioceptive deficits, what are differentials for neurolocalizaiton?
* right motor cortex * right corticospinal tract * left cervical spinal cord
26
When assessing physiologic nystagmus, what reflex is assessed?
Vestibuloocular reflex
27
What are the hallmark signs of cerebellar disease?
* wide-stance ataxia * dysmetria (inappropriate measure of muscle contractions) - exaggerated goose-stepping * asynergia * Intention tremors
28
Where do the sympathetic and parasympathetic nervous systems originate?
sympathetic - thoracolumbar spinal cord parasympathetic - brainstem and sacral spinal cord
29
What 3 tissues does the autonomic nervous system affect?
* smooth muscles * glandular tissue * cardiac muscles
30
Which cranial nerves are part of the parasympathetic system?
* oculomotor (CN III) * facial (CN VII) * glossopharyngeal (CN IX) * vagus (CN X)
31
What nerves are formed by the sacral part of the parasympathetic nervous system?
pelvic nerves
32
How is norepinephrine removed from the synpatic cleft?
reuptake by the presynaptic neuron
33
How are norepinephrine and epinephrien removed from the circulation?
enzymatic breakdown * catechol-O-methyltransferase * monoamine oxidase highest cc in liver and kidneys
34
What are the two different receptors stimulated by acetylcholine?
**Muscarinic** acetylcholine receptor * G-protein couple * target cells of postganglionic parasympathetic neurons and cholinergic postganglionic neurons of the sympathetic nervous system **Nicotinic** receptors * ligand-gated ion channels * at synapses between autonomic preganglionic and postganglionic neurons * at somatic neuromuscular junctions
35
Why does sympathetic stimulation typically last longer than parasympathetic stimulation?
because of circulating norepinephrine and epinephrine
36
Describe how urine storage is facilitated
facilitated mainnly by the **sympathetic nervous system** * lumbar splanchnic nerves - inhibits contraction of the destrusor muscle * inhibit parasympathetic postganglionic neurons that would otherwise cause detrusor contraction * contracts smooth muscle internal sphincter (neck of bladder) * **somatic motor neurons** >> external sphincter contraction (urethralis muscle)
37
Describe how urine voiding is facilitated
* contraction of the detrusor muscle via parasympathetic nervous system (pelvic nerves) * inhibition of sympathetically mediated storage reflex both controlled by the pontine micturition center (PMC) PMC can be overriden by conscious control
38
What structures must be intact for a normal direct PLR response?
* retina * CN II * CN III * brainstem * iris
39
How is aqueous humor formed?
active transport of Na, Cl, HCO3- into the posterior chamber >> draws in water flows from posterior into anterior chamber due to pressure gradient absorbed into the venous system at the angle between the cornea and the iris
40
Where is CSF formed?
choroid plexus of the ventricles
41
List 3 functions of the CSF
* cushions the brains against trauma * helps maintain a consistent EC environment for neurons * removes potentially harmful cellular metabolites
42
What are the 4 ventricles?
* 2 lateral ventricles, left and right * third ventricle at the midline of the diencephalon * fourth ventricle: between cerebellum and dorsal surfac of hindbrain
43
How does blood pressure of CSF pressure affect CSF formation?
independent - formation is almost constant
44
Name 3 drugs that could reduce CSF production/volume
* acetazolamide (carbonic anhydrase inhibitor) * furosemide * PPIs - proton-pump inhibitors (reduce NaKATPase activity in the choroid plexus)
45
What characteristics facilitate the BBB selectivity?
* tight junctions * no open clefts (usually present in capillaries in other organs)
46
What molecules can cross the BBB easily?
* lipophilic * minimally protein-bound * small and uncharged otherwise >> carrier-mediated transport
47
What are the parts of the neuromuscular bundle?
* surrounding pericytes * glial astrocytic "end-feet" * neurons
48
How can you measure CSF pressure and what is normal in dogs?
manometer through a needle placed in the cisterna magna normal < 180 mm CSF

Boards: Neurology + Ophthalmology (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions