Topic 10: Spinal cord, brain stem, diencephalon, cerebrum Flashcards
(129 cards)
1
Q
4 main components of the spinal cord
A
- conus medullaris
- filum terminale
- cauda equine
- cervical/lumbar enlargements
2
Q
component of the spinal cord that tapers into the inferior end of the spinal cord
A
conus medullaris
3
Q
component of the spinal cord that is long connective tissue filament that extends from the conus medillaris to coccyx and anchors the spinal cord in place
A
filum terminale
4
Q
component of spinal cord that is a collection of spinal nerve roots in inferior end of the vertebral canal
A
cauda equine
5
Q
component of the spinal cord that is where the nerves of upper and lower limbs arise
A
cervical/lumbar enlargements
6
Q
in which direction is the spinal cord the widest?
A
laterally
7
Q
3 major function of the spinal cord
A
- attaches to spinal nerves and are involved in sensory and motor innervation of body below head
- provides a two-way conduction pathway for signals between the body and brain
- major center for reflexes
8
Q
location of the spinal cord
A
vertebral foramina
9
Q
extension of spinal cord in infants
A
foramen magnum to L3
10
Q
extension of spinal cord in adults
A
foramen magnum to L1/L2
11
Q
how many total pairs of spinal nerves in PNS?
A
31 pairs
12
Q
Where do spinal nerves attach to the spinal cord
A
dorsal and ventral roots
13
Q
how many spinal nerve pairs in the cervical vertebrae?
A
8
14
Q
how many spinal nerve pairs in the thoracic vertebrae?
A
12
15
Q
how many spinal nerve pairs in the lumbar vertebrae?
A
5
16
Q
how many spinal nerve pairs in the sacral vertebrae?
A
5
17
Q
how many spinal nerve pairs in the coccygeal vertebrae
A
1
18
Q
in what anatomical direction is the corresponding spinal nerve in relation to the the invertebral foramina located? and Why?
A
superior
spinal cord doesn’t extend all the way down the vertebral column
19
Q
in what vertebral level is spinal cord segment T5 located?
A
T4
20
Q
in what vertebra level is spinal cord segment S1 located?
A
L1
21
Q
what indicates the region of the spinal cord where the spinal nerves fibers first emerge?
A
spinal cord segments
22
Q
What two grooves in the spinal cord divide it into left and right halves? Which is wider?
A
- dorsal (posterior) median sulcus
- ventral (anterior) median fissure WIDER
23
Q
white matter fibers that carry sensory information from sensory neurons to the brain
A
ascending fibers
24
Q
white matter fibers that carry motor information from brain to the spinal cord to stimulate muscle contraction or gland secretion
A
descending fibers
25
white matter fibers that carry information from one side of the spinal cord to another
commissural fibers
26
component of white matter in which bundle of axons crosses from one side of the CNS to another
commissure
27
main function of spinal cord
communication within spinal cord and between brain and spinal cord
28
3 funiculi of white matter
1. dorsal (posteior) funinculus
2. ventral (Anterior) funinculus
3. lateral funinculus
29
what are the 7 components of gray matter in the spinal cord
-gray commissure
-dorsal horns
-ventral horns
-lateral horns
-dorsal root ganglia
-dorsal root
ventral roots
30
component of gray matter that is the cross-bar of the H, contains unmyelinated axons, narrow central cavity cavity (central canal)
gray commissure
31
component of gray matter posterior arms of H; run as column entire length of spinal cord; interneurons receive info from sensory neurons
dorsal horns
32
component of gray matter anterior arms of H; run as a column the entire length of spinal cord, contain cell bodies of motor neurons and interneurons; largest in cervical and lumbar segments--innervate upper and lower limbs
ventral horns
33
component of gray matter with small lateral columns in the thoracic and superior lumbar segments of spinal cord and contain cell bodies of motor neurons and interneurons
lateral horns
34
component of gray matter that is the location of sensory neuron cell bodies (outside the spinal cord)
dorsal root ganglia
35
component of gray matter that connects sensory neuron to the spinal cord
dorsal roots
36
component of gray matter that sends motor neuron axons to supply muscle and glands
ventral roots
37
dorsal sensory half of gray matter
- SS (somatic sensory)
| - VS (visceral sensory)
38
ventral motor half of gray matter
- VM (visceral autonomic motor)
| - SM (somatic neuron)
39
loss of sensory function; caused by damage to the dorsal horn or sensory neuron cell bodies in dorsal root ganglia
paresthesia
40
disorder caused by damage to the ventral horn or ventral motor roots destroying the motor neurons
paralysis
41
3 things that protect the spinal cord
1. vertebrae
2. meninges
3. CSF
42
3 connective tissue membranes that compose the meninges
1. dura mater
2. arachnoid mater
3. pia mater
43
order of meninges tissue membranes from internal to external?
1. Pia mater
2. Subarachnoid space
3. Arachnoid mater
4. Subdural space
5. Dura mater
6. Epidural space
44
fat-rich cushioning space external to dura mater
epidural space
45
most external layer; strongest layer of meninges, single leathery layer of dense fibrous connective tissue surrounding CNS (extend to level of S2)
dura mater
46
thin-fluid filled space in btw dura mater and arachnoid mater
subdural space
47
layer lies deep to the dura mater (extend to level of S2)
arachnoid mater
48
filled with CSF and large blood vessels; spanned with web-like threads that anchor the arachnoid mater to the pia mater
subarachnoid mater
49
innermost layer of meninges; clings tightly to the surface of the spinal cord, layer of connective tissue, vascularized w/small blood vessels, extends to the coccyx covering the filum terminate; denticulate ligaments anchor spinal cord laterally to the arachnoid and dura mater throughout the length of the cord
pia mater
50
watery fluid that fills the subarachnoid space and hollow cavities of the brain and spinal cord
CSF
51
function of CSF
provides liquid cushion and buoyancy for the spinal cord and brain, nourishes brain and spinal cord, removes wastes produced neurons, carriers chemical signals between parts of the CNS
52
location of a lumbar puncture/spinal tap
(L1-L2)
53
4 things that protect the brain
1. skull
2. meninges
3. CSF
4. Blood-brain barrier
54
2 layers of dura mater
1. periosteal layer
| 2. meningeal layer
55
two dural sinuses
1. dural sinuses
| 2. superior sagittal sinus
56
outer layer of dura mater that attaches to the internal surface of the skull bones
periosteal layer
57
deeper layer of dura mater which forms external covering of the brain and is continuous the with dura mater that surrounds the spinal cord
meningeal layer
58
sinuses in the dura mater that collect blood from the brain and conduct it to the large internal jugular veins of the neck
dural sinuses
59
sinuses in the dura mater that are their largest dural sinus and is positioned in the superior midline
superior sagittal sinus
60
function of arachnoid villi
act as valves that allow CSF to bass from subarachnoid space into dural blood sinuses
61
location of arachnoid villi
project through the dura mater over the superior part of the brain into superior part of the brain into suoeior sagittal sinus and other dural sinuses
62
inflammation of meningeal tissues from infection
meningitis
63
inflammation of brain or spinal cord from infection
encephalitis
64
weight of average adult brain
1500 grams
65
main functions of the brain
-preforms the most complex neural functions: intelligence, consciousness, memory, sensory-motor integration, cranial nerves involved in innervation of the head
66
which two body systems does the brain control and maintain?
autonomic nervous system and endocrine system
67
during what week of embryonic development does the brain arise from rostral part of the neural tube, caudal position becomes spinal cord
week 4
68
what are the three primary brain vesicles? and where are they located
- Prosencephalon--the forebrain
- Mesencephalon--the midbrain
- Rhombencephalon--the hindbrain
69
during what week of embryonic development does secondary brain vesicles emerge
week 5
70
what does the prosencephalon divide into?
telencephalon and diencephalon
71
what does the mesencephalon become?
remains undivided
72
what does the rhombencephalon divides into?
metencephalon and myelencephalon
73
what adult brain structures does the telencephalon develop into?
cerebral hemispheres
74
what adult brain structures does the diencephalon develop into?
thalamus, hypothalamus and epithalamus
75
what adult brain structures does the mesencephalon develop into?
midbrian
76
what adult brain structures does the metencephalon develop into?
pons and cerebellum
77
what adult brain structures does the myelencephalon develop into?
medulla oblongata
78
brain structures from rostral and caudal
```
cerebrum
diencephalon
cerebellum
brain stem
caudal
```
79
ventricles of the brain located in telencephalon; horseshpe shaped bending of cerebral hemispheres
paired lateral ventricles
80
what is each lateral ventricle composed of?
- anterior horn
- posterior horn
- inferior horn
81
what separates the anterior horn of each lateral ventricle
septum pellucidum
82
what lies in the roof of the paired lateral ventricles?
choroid plexus
83
what ventricle lies in the diencephalon?
3rd`
84
what connects the 3rd ventricle to the lateral ventricles?
interventricular foramena
85
what connects the 3rd and 4th ventricles?
cerebral aqueduct
86
what lies in the roof of the 3rd ventricle/ cerebral aqueduct?
choroid plexus
87
location of the 4th ventricle?
hindbrain
88
what are the three apertures of the 4th ventricle
- paired lateral apertures (side walls)
| - median aperture (roof)
89
what lies in the roof of the 4th ventricle?
choroid plexus
90
location of most CSF formation from blood plasma
choroid plexus
91
components of CSF
- glucose
- oxygen
- vitamins
- ions e.g. Na, Cl, Mg
92
CSF movement (4 steps)
1. CSF enters ventricles
2. enters subarachnoid space through the lateral and median apertures in the walls of the 4th ventricle
3. Flows through subarachnoid space and bathes cells
4. passes through arachnoid villi and is absorbed into the blood throug h the venous dural sinuses
93
rate of CSF cycling
500 ml/day
94
excessive accumulation of CSF in ventricles and/or subarachnoid space
hydrocephalus
95
function of the blood brain barrier
prevents some blood-borne toxins and some drugs from entering the brain
96
what can pass through the blood brain barrier?
oxygen, fat soluable molecules like alcohol, nicotine and anesthetics
97
what % of brain mass is the brainstem?
2.5%
98
what three structures make up the brain stem?
midbrain, pons and medulla oblongata
99
main functions of brainstem?
- passage for fiber tracts running through cerebrum and spinal cord
- innervation of face and head
- automatic behaviors
100
ratio of cranial nerves associated with the brain stem
9 out of 12
101
most rostral region of the brainstem
midbrain
102
midbrain lies between?
pons and diencephalon
103
central cavity of the midbrain
cerebral aqueduct
104
ventral surface of the midbrain?
cerebral peduncles contain pyramodial tracts descending from cerebrum to the spinal cord
105
ventral part of each penducle is called?
crus cerebi
106
surrounds the cerebral aqueduct in the midbrain
periaqueductal gray matter
107
periaqueductal gray matter function
involved in sympatheitc reaction
| mediates response in visceral
108
the largest brain nuclei which make up the tectum (roof) of dorsal midbrain and form four bumps on the dorsal midbrain
corpora quadrigemina
109
two colliculi of midbrain and what are their function
1. superior colliculi
| 2. inferior colloculi
110
gray matter is embedded in midbrain, contain cell bodies melaninin in band-like distrubtions
substantia nigra
111
location substantia nigra
positioned deep to pyramdial tracts of cerebral peduncle
112
degeneration of neuron in the substantia nigra contributes to which neurological disorder?
Parkinson's disease
113
gray matter that is in midbrain white matter
red nucleus
114
location of red nucleus in midbrain
lies deep to substantia nigra
115
what gives the red nucleus it's red color?
rich blood supply and presence for iron pigment in neuron cell bodies
116
a bulge in the in the brainstem between the midbrain and medulla oblongata
pons
117
conical shaped, most caudal level of the brainstem, that is continous with the spinal cord at level of foramen magnum skull
medulla oblongata
118
large wavy fold of gray matter in medulla oblongata
olive
119
function of olive in medulla oblongata
relay station for sensory information traveling to cerebellum, especially for proprioceptive information ascending from the spinal cord
120
function of pyramid tracts
carrying voluntary motor output from the cerebrum to the spinal cord
121
crossing over motor tracts enable each cerebral hemisphere to control the voluntary movements of the opposite side of the body through this processes
decussation of the pyramids
122
loose cluster of brain nucleu that run through the core of the brainstem to stimulate cerebral alertness and regulate muscles
reticular formations
123
what % of brain mass is the cerebellum
11%
124
smoothes and coordinates body movements directed by other brain regions, helps maintain posture and equilibrium
cerebellum
125
cerebellar hemispheres connected medially by?
vermis
126
cerebellar hemispheres subdivided into which three lobes
anterior lobe, posterior lobe, flocculonodular lobe
127
outer gray matter which is a neuron rich calculator that smooths out body movements
cereberal hemisphere cortex
128
internal white matter rich in axons which carry information to and from the cortex
arbor vitae
129
surface of cerebellum folded into ridges called?
folia
