Exam 2(CNS structures) Flashcards
(121 cards)
1
Q
Fiber classification
A
A- fastest and largest class(myelinated)
descending size of A-alpha>beta>gamma>delta
B- lightly myelinated neuron
C- Slowest and not myelinated
smaller and slower
2
Q
Soma
A
Cell body of neuron
building and decision making center of the cell
3
Q
Dendrites
A
Project from cell body to receive stimulus from nerve/or outside sitm
not myelinated
more positive the dendrite, the more excitable/receptive dendrite is
4
Q
Axon
A
myelinated to send AP quickly
nodes of ranvier(AP jumps npode to node)
presynaptic terminal is the end of axon
hillock for inhibition
5
Q
Axon Hillock
A
Suppress neuron activity here(only inhibitory)
GABA dependent–receptors on axon hillock increase chloride permeability and increase chloride permeability will inactivate cell
No GABA/no inhibition at the hillock
6
Q
Glial Cells
A
Large and small, proliferative
astrocytes
ependymal cells
oligodendrocytes/schwann cells
microglia
7
Q
Microglia
A
Digest what needs to be broken down
macrophage of CNS
smallest glial cell
8
Q
Astrocytes
A
Big part of BBB/technically not
astrocytes attach to endothelial cells/capillaries(BBB) in CNS and tight junctions keep barrier
helps maintain electrolytes and pH in the CSF
9
Q
Ependymal Cells
A
CNS cells with cilia
motility structures move CSF down the cns and is pushed up to brain
10
Q
Oligodendrocytes
A
Myelin producing cells in CNS
Schwann cells are PNS counterpart
11
Q
Multipolar Neuron
A
Decision making cell
take in a lot of info through the dendrites on one side/then soma/then axon/presynaptic
Will send signal through axon
Decide and communicate
12
Q
Bipolar
A
specialized sensory cell
Dendrite, axon, soma, axon, presynaptic
no decision making/just sense and send
photoreceptors of retina/optic nerve
13
Q
psaudounipolar
A
sensory function, send through cell
sensory cells in spinal cord/immediately outside are pseudounipolar
just a messenger
found near spine/cns
soma just for support of structures in cell
14
Q
Nociceptor
A
pain receptor for transducing pain/sensing pain
15
Q
mechanoreceptor
A
physical disturbance turns to electrical signal
sense types of pressure
16
Q
Chemical synapses
A
electrical signal relayed by chemical intermediary called neurotransmitter(ACh)
17
Q
Planes/cross sections of the body
A
Sagittal–left from right
Coronal–anterior from posterior
horizontal plane–superior from inferior
Oblique–all other angles
18
Q
CNS divisoins
A
Telencephalon–cerebral hemispheres and cerebral cortex
Diencephalon–inner brain/between telencephalon and brain stem includes
-thalamus-relay center between cerebreal hemispheres and rest of body
-hypothalamus-under thalamus/deep to thalamus/ sensory area and controls
-body temp
-osmol
-infection
Brain stem
-midbrain-mesencephalon(top of brain stem)
-pons-olive big structure
-medulla oblongata
spinal cord
19
Q
Frontal Lobe
A
thinking/inner thought
20
Q
Parietal lobe
A
sensation processing behind frontal lobe
21
Q
Occipital lobe
A
Rear of brain/primary visual cortex
22
Q
Temporal Lobes
A
lateral sides/processes hearing/comprehension/music
23
Q
Central sulcus
A
groove between frontal/parietal
24
Q
temporal/temporolateral fissure
A
below central sulcus/
splits temporal from frontal and parietal lobes
25
Longitudinal fissure
Deep groove splitting left and right/whole outer brain split
26
Precentral gyrus
primary motor cortex/rear part of frontal lobe
27
Post-central gyrus
anterior part of parietal lobe
somatosensory area
28
Corpus callosum
pathway of white matter between right and left brain/important communication
29
Grey matter/white matter of brain and why
grey matter on outside/inner white matter
grey matter has lots of thinking and lots of blood flow/thats why its on outside even though less protected than white matter inside
30
Lamina 10
grey matter in splitting middle of spinal cord
has central canal in middle for CSF movement down cord
31
Grey matter of spinal cord
Dorsal horns of back--recieve sensory information through rear
Ventral horns-front grey matter and sends motor function/wider than the dorsal horn
32
Anterior white commissure
area of white matter in front of lamina 10/middle of spinal cord
33
Posterior median sulcus/fissure spinal cord
Anterior median sulcus/fissure
posterior-deep groove in back very narrow
anterior-front deep grove/wider than back for large arterial blood vessel
34
Spinal cord arterial blood supply
posterior spinal arteries(2) are leteral from central
anterior spinal artery is midline and up anteror central sulcus(sulcal arteries go into sulcus)
Intercostal artery had blood flow directed toward cord
35
Spinal cord venous drainage
posterior spinal vein/anterior spinal vein both midline
36
Descending pathway of motor function
starts in frontal lobe/at precentral gyrus
descends through white matter of brain through midbrain/into lateral spinal cord/then into ventral horn and out of cord/down axons of the anterior rootlet into anterior root and into spinal nerve
37
Ascending sensory pathway from spinal nerve
spinal nerve feeds into posterior root with ganglion/into posterior rootlet/into grey matter of ventral horn/then sent to ascending portions of spinal cord white matter(mostly ventral/posterior and outside edges)/ ends in parietal lobe at postcentral gyrus
38
Spinal ganglion of posterior root
Pseudounipolar sensory neuron bodies create this "lump"
recieve signal and then axon sends through posterior rootlet to dorsal horn of grey matter
39
Descending spinal tracts
motor pathways are in lateral and frontal/anterior aspect of spinal cord
40
Cervical Nerve anatomy
7 vertebrae/8 spinal nerves come off cord above corresponding vertebrae except 8 which comes below C7
41
thoracic/lumbar spinal nerve anatomy
Thoracic has 12 vertebrae/12 spinal nerve pairs that come under corresponding vertebrae
lumbar has 5 vertebrae with 5 spinal nerve pairs under corresponding vertebrae
42
Sacrum Nerve anatomy
5 vertebrae that fuse into one solid bone/5 nerve pairs named for "vertebrae" above
43
Coccygeal spinal nerve anatomy
Starts as 4 vertebrae then fuses into 2 vertebrae/last pair of spinal nerves
44
Spinal curvature
Cervical--convex from front/lordosis
Thoracic--concave from front/kyphosis
Lumbar--convex from front/lordosis
Sacrum/coccygeal--concave from front/kyphosis
Pathologic curvature is scoliosis to R or L/ and could be over curved at any level/kyphoscoliosis is both
babies are born with solely kyphotic curvature
45
Basic Vertebral Anatomy
Vertebral Body
Vertebral Arch(pedicle is base and lamina is arch)
Superior Articular process(fits with inferior)
Inferior articular process
Transverse Process(lateral)
Spinous process(posterior)
46
Where does the spinal nerve leave vertebrae(generally)
Leaves below pedicle in inferior vertebral notch
47
Unique C-spine vertebrae features
Bifid C2-5(50% 6)
Transverse foramen for vertebral arteries(except C7 has foramen but artery doesn't pass through)
Transverse process has sulcus for spinal nerves(come out above corresponding vertebrae)
Larger vertebral foramen/smaller vertebral body
48
C1 name and details
"Atlas"
No vertebral body (not much weight)/posterior tubercle instead
Anterior tubercle has facet for dens(cylinder structure on C2)
Superior articular facet-fits the base of the skull
49
Base of skull features
Foramen magnum(large opening at base)
Occipital condyles(part of occipital bone) project downward(sit in superior articular facet)
Atlantooccipital ligament--anterior and posterior/both connect through the foramen magnum
50
Skull/Spine Articulation
C2 had dens which projects into C1 and sits in anterior tubercle in facet of dens/skull sits on C1 in the superior articular facet
51
C2 special features
Dens--projection from anterior side that fits into C1(facet of dens), anterior articular facet on dens sits there
52
Anterior Longitudinal ligament
along anterior vertebral bodies from skull to sacrum/strong and not flexible
53
Posterior longitudinal ligament
posterior to vertebral body (inside vertebral foramen) and skull to sacrum
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Inter-transverse ligament
Transverse process to transverse process
55
Supraspinous ligament
spinous process tip to spinous process tip(superficial edge)
56
Interspinous ligament
connects spinous process to spinous process midline/not in lamina portion of vertebral arch
57
ligamentum flava
Connects vertebral arch to vertebral arch
stretchier than other ligaments
feels different with a needle because not as fibrous
used as a feel marker for needle access
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Flava
opening between ligamenta flava, this is important because needle approach must be slightly offset to hit ligamentum
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Neck ligament specialization
Expansion of posterior ligaments
Interspinous ligament expansion and is called nuchal ligament/same but bigger
60
Anterior atlantooccipital membrane
connects C1 arch to opening of foramen magnum
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External occipital protuberance connection
nuchal ligament connects here at back of head
62
Vertebral Prominenece
bump at base of neck
C7 by textbook
T1 spinus process is generally larger
63
T-Spine number of vertebrae
curve
unique features
12 vertebrae
kyphotic curve
Ribs come off each of the T spine at costal facets
downward spinal processes
rounded R side of heart vertebrae, flat L side for aorta
64
Parts of the sternum
Manubrium
body
xiphoid process
65
Categorize ribs
True ribs--1-7 rib to cartilage to sternum
False ribs-- 8-10 connect to cartilage of rib 7
Floating ribs--one connection and do not connect to the sternum or cartilage
66
Describe the Rib Vertebrae connection
Costal facet on vertebral body
superior sits with matching rib, inferior with rib below/connects to head of rib
transverse process has costal facet/connects to costal tubercle
67
Lumbar spine vertebrae characteristics
Spinous process is straight back so can access CNS
large vertebral body because weight
lordodic
68
Sacrum Characteristics
Promontory--disk sits here to support L5
fused together so sacral foramina is where nerves come out(as opposed to intervertebral foramina)8 total/4 front/4back
continuous sacral canal
sacral hiatus is hole at bottom where coccygeal spinal nerve leave
sacral conus is projectoins off hiatus
69
Crests of Sacrum
Median is middle
lateral is outside formed by transverse processes fusing
medial is superior/inferior process fusing
70
Coccygeal Vertebrae
1 stays on own
2-3-4 fuse together to form 2 total vertebrae
71
Iliac crest point on spine
L4
72
Posterior superior iliac spines
prominent ridges on lower back
marker to access S2 foramens(1cm midline, 1cm down)
blocks of lower limbs
73
Top front of pelvis
anterior superior iliac spine
74
Inguinal ligament
attaches superior iliac spine to pubic tubrecle
75
Iliolumbar ligament
connects L4/5 transverse process to back of pelvis
76
pubic symphysis
cartilage between two sides of pelvis
77
Supraspinous ligament
tip of spinous process to coccyx
78
bottom set of hips
greater trochanter part of femur
79
Parts of intervertebral disk
annulus fibrosus is is tough surrounding criss crossed anteriorly, less stable posteriorly
nucleus pulposus--gel like middle of intervertebral disk
no intervertebral disk sacrum once fused
80
Hyaline Cartilage
end plate on vertebral body
81
Why are disk herniations possible/why do they hurt so much
back nucleus pulposus weaker and spinal nerve in intervertebral foramen is squished by the nucleus pulposus pushing back
82
3 options for disk herneation
Discectomy--remove disk
spinal fusion--stabilize vertebral body by connecting two but adds stress to surrounding disks--successful but lasts only 6-7 years
Laminectomy--remove portion of lamina to relieve compression but not very successful
83
Pia mater
tight surrounding to neurons/glial cells
84
Arachnoid mater
superficial to pia but room for CSF and large blood vessels, possible subarachnoid arterial bleeds
85
Dura layer
superficial to arachnoid layer and there is no room between(unless a subdural venous bleed)
86
Where does the dura layer extend to
extends to beginning of spinal nerve and down to sacral foramen?
87
Epidural space
adipose tissue with venous blood vessels right outside dura
88
Epidural considerations
park needle in blood vessel and fatty tissue area to shut down spinal nerves
lipophilic anesthetic could be taken up here which will take longer but will last longer because saturated
use section of spine without spinal cord
89
Spinal Cord goes from medulla to
L1, called the conus medullaris
90
two enlargements of spinal cord and locations
Cervical enlargement C3-C6
motor sensory input for upper extremities
Lumbar Enlargement- T11-L1
motor and sensory neurons for legs
91
Cauda Equina
Inferior nerve roots below conus medullaris
"horses tail"
92
Filum Terminale internum
Filum Terminale externum
internum is extension of pia mater and connects end of spinal cord to dural sac to keep cord length
externum--bottom of dural sac (S2) anchor to sacrum bottom
93
dural sac
area between conus medullaris and houses cauda equina, extends to S2 from L1
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Newborn V Adult conus medullaris
L1 in adult/L3 in newborn but spine grows faster than cord
95
Lumbar cistern
area below conus medullaris
CSF and spinal nerves but no spinal cord, CSF does not refresh as frequently here but is easier to access for lumbar puncture
96
Spinal puncture/procedure areas
between L3/L4
or L4/L5
or can access sacral hiatus
Posterior sacral foramina--S2
use posterior superior iliac spine and go 1cm down/1cm midline
97
What degree angle should you approach spine/epidural
15 degrees should be enough to catch ligamentum flavum so as to not go to far
98
Connective tissue surrounding CNS
pia mater--directly close to glial cells/neurons
arachnoid mater--superficial to pia but has room for large blood vessels in CNS and spinal fluid under it
dura mater-superficial to arachnoid, subdural isnt truly a space. sinus's of the brain are made from this
99
Contents of epidural space
fatty and has venous blood vessels
lipophilic anesthetics will take more and last longer because of adipose tissue
100
Spinal cord start and end
2 enlargements
Spinal cord goes from medulla to L1
end of spinal cord is conus medullaris
Cervical enlargement for upper extremities is C3-C6
Lumbar enlargement T11-L1
101
Dura layer covers--
Brain, spinal cord, down to bottom of sacrum and to spinal nerves(rootlets covered)
102
Cauda equina
Dorsal and ventral nerve roots that come off conus medullaris
103
Arachnoid trabeculae
Keep the space between pia and arachnoid/ creating the area for CSF and vasculature
104
CSF pH/buffer system/Na/Cl/K/Mag/Glucose
quantity/how much is produced in a day
7.31
Co3- as buffer(lower than plasma)
140 Na
140 Cl(match Na)
40%less K
higher Mag
60 mg/dL glucose(90 in body)
150mL total
produce 500mL in a day mostly refreshing brain while lumbar cistern is slower
105
Ependymal cell
Separate CSF from CV system
Na>>into cell>pumped into CSF
Cl>>into cell>follows Na
H20>>into cell>follows Na
all dependent on Na/ATP pump
106
Choroid plexus function and location
Many ependymal cells that produce CSF
in each of the 4 ventricles of the brain
107
CSF flow from Lateral ventricles
interventricular foramen of monroe
into ventricle 3
into cerebral aqueduct of sylvis
(most likely to be blocked)
into ventricle 4
108
exit points of CSF from brain(ventricle 4)
Central canal to spinal cord
Lateral apertures/ foramen of lushka
median aperture/foramen of magendie
goes to cerebellum
109
Communicating v noncommunicating hydrocephalus
communicating--pathways are okay but the blockage is outside the ventricles/apertures
non-communicating--blockage within the system
110
Names and location of cranial blood drainage
Cranial sinuses
Superior sagittal sinus--top and midline
inferior sagittal sinus--below superio/midline
straight sinus--end of inferior sinus
straight sinus and supeiror sinus form confluence of sinuses
transverse sinus--exit point of confluence of sinus to sigmoid
sigmoid sinus sharp turn to jugular foramen
and down internal jugular
111
Falx cerebri
Tentorium cerebelli
Falx cerebri--connective fan like tissue between cerebral hemispheres
Tentorium cerebelli--connective tissue supporting occipital with cerebellum below
112
Arterial blood supply of brain
2 vertebral arteries feed back of brain
2 internal carotid arteries feed anterior brain
2 external carotid feed superficial structures
amounts to 750mL/min blood flow
about 15% of CO
50mL/min/100g of tissue
flow will match metabolic demand
113
Distribution of blood flow to brain
80% blood flow feeds grey matter 20%feeds white matter
114
Circle of Willis arteries
Middle cerebral artery fed by carotid
Anterior cerebral artery/specifically A1 portion/precommunicating
connect left and right with anterior communicating artery
Posterior cerebral artery/specifically P1/precommunicating/
connected to middle cerebral artrey by posterior communicating artery
115
Cerebellar Arterial blood supply
Superior cerebellar artery--perfuses front and top of cerebellum/comes of basilar artery
anterior inferior cerebellar artery--comes off basilar artery
posterior inferior cerebellar artery comes off vertebral arteries for lower cerebellum
116
Largest Deep artery of brain
middle cerebral artery branches out and would create massive amount of damage
117
Area of bran perfused by anterior, middle, and posterior cerebral artery
Anterior--central line
Middle--lateral and central
Posterior
occipital and lower
118
Subarachnoid hemorrhage
ruptured aneurism
infiltrate glial and neural cells
progress quickly/ "hemorrhagic strokes"
118
Subdural Hematoma
Generally venous/dura wall of sinous rupture
slower to develop
118
Epidural hematoma
Above dura mater
most likely traumatic/skull fracture
quick because arterial blood supply in skull
119
