? separates the cerebral cortex above and the cerebellum below
tentorium cerebelli
basement membrane also called
neurolemma/or endoneurium. found only in pns
connective tissue cells of the nervous system, don't conduct impulses, nervous system matures due to an increase in these cells. most numerous in the nervous system
neurolglial cells
3 diff neuroglial cells in cns
oligodendroglia, astocytes, microglia
smaller fewere, some are around axon, some in rows, between nerve fibers to hold fibers together
oligodendroglia
produce multiple myelin segments (covers nerve fibers in brain and cord)
oligodendroglia
? disease of oligoden
multiple sclerosis
largest form sheath around brain capillaries; involved with brain barrier; allow nutrients in, waste out; produce scar tissue where CNS tissue removed
astrocytes
small stationary cells, brain inflamed, phago microbes and cell debris
microglia
form epithelial lining for fluid-filled ventricles of brain for central canal of cord
ependymal cells
around cell bodies in the PNS, in ganglia so supportive and physical barrier function
satellite cells
? found only in nerves of body (PNS), form basement membrane and myelin sheath, can regenerate because of 2nd covering
Schwann cells
? controls motor
frontal
? controls sensory
parietal
? controls hearing
temporal
? controls vision
occipital
? controls emotions and memory
limbic
? controls somatic and visceral function
insula
dorsal =
posterior
ventral =
anterior
input to cord is by incoming sensory in the...
posterior root of spinal nerve
the sensory cell body is located in the ?
posterior root ganglia = swelling near cord
afferent synapse occurs in the ?
posterior horn of the gray matter
? these neurons synapse with incoming and outgoing neurons
interneurons
out put from the ant horn of the gray matter is by the
motor or efferent neurons out the ant root of the spinal nerve
consists of tracts or columns (asced/desced)
white matter
conduct pain temp, crude touch, tickle, itch and sex sens to thalamus
lat spinothalamic tracts
conduct pain temp, crude touch, tickle, itch and sex sens from cord to thalamus
ant spinothalamic tracts
post columns for discriminating touch, and proprioception
fasciculi gracilis and cuneatus
sensory component of the muscular system, sense of movement and body parts
proprioception
for unconscious kinesthesia
spinocerebellar tracts
impulses down the cord from the brain are
motor
axons from cell bodies in the cerebral cortex to the cord, for precise discrete, voluntary movement on the opposite side of body
lateral corticospinal tracts
lateral corticospinal tracts cross in the
medulla pyramids
ant corticospinal tracts
axons from cell bodies in the cerebral cortex to the cord, for precise discrete, voluntary movement on the opposite side of body
ant corticospinal tracts cross in
the cord
lat reticulspinal tracts
facilitatory impulses to ant gray horn motoneurons to skeletal muscles
medial reticulspinal tracts
inhibitory impulses to ant gray horn motoneurons to skeletal muscles
surround the cord
meninges
collagenous conn tissue, stong durable
dura matter
true epidural space around the dura of the
spinal cord, not the brain, dura attaches to bone
arachnoid membrane
encloses the subarachnoid space
subarachnoid space is filled with
csf
covers organs of the cns and extends beyond the cord to anchor it, carries blood vessels into the brain and cord, inner most
pia mater
denticulate ligaments ?
thickening of Pia that fuses with arachnoid + dura mater that projects laterally b/n spinal nerve roots and protects against shock and sudden displacement
? where cord ends
at lumbar 2 vertebrae
spinal nerve C8 merges ?
between C7 and T1
how is CSF formed?
by the filtration of blood in the choroid plexuses
choroid plexuses?
network of capillaries from the Pia Mater into the ventricles
how does CSF travel?
from lateral ventricles to the the interventricular foramen into 3rd ventricles into Cerebral Aqueduct of Sylvius into 4th ventricle, then into central canal of the cord and subarachnoid spaces
how is CSF absorbed?
absorbed back into the blood thru the Arachnoid Villi (granulations) into venous sinuses
what is the purpose of CSF?
functions as a protective cushion
Glutamic acid and Aspartic acid =
excitatory NT
GABA and Glycine =
inhibitory NT
Norepinephrine =
monoamine for arousal
dopamine =
monoamine for movement and emotions
Enkephalins and Endorphins =
body opiates that inhibit pain
Substance P =
body opiate that controls pain in the cord
most common NT =
Acetylcholine (ACh)
where are NTs synthesized?
axon terminals by enzymes
NTs are stored in...
axon terminals
? cerebellum receives a lot of input from...
vestibular system (inner ear). Also propeoceptors, cortex, and reticular system
Cerebullum functions:
coordinates and controls smooth muscle movement and postural and equilibrium reflexes
large, rounded mass of gray matter lateral to 3rd ventricle, 1 in each hemisphere.
Function of Thalamus is ? (4 of them)
major sensory relay center= recognizes pain, heat, cold, touch, and pressure; involved in expressing emotions associated with sensations; partly involved in arousal and alerting mechanisms and complex reflex movement.
Function of Hypothalamus is ? (8 of them)
regulates and coordinates the ANS, regulates pituitary's function, regulates temp, regulates water balance by checking blood's osmotic pressure, controls food intake, regulates gastric secretions, emotional expression of rage, anger, and sexual behavior,
Structure of Hypothalamus:
includes gray matter around the optic chiasm, pituitary stalk, posterior lobe of the pituitary, mamillary bodies, and adjacent regions.
CN1
olfactory; smell; sensory
CN2
optic; sight; sensory
CN3
oculomotor; eye movement and focusing; motor
CN4
trochlear; eye movement and focusing; motor
CN5
trigeminal; sensory for head and neck, face and chewing; sensory and motor
CN6
abducens; eye movement and focusing; motor
CN7
facial; taste (ant. 2/3 of tongue) and face muscles and glands; sensory and motor
CN8
acoustic/vestibular cochlear; hearing and posture, balance; sensory
CN9
glossopharyngeal; swallowing and taste (posterior 1/3 of tongue); motor and sensory
CN10
vagus; important in ANS, sensory, and motor to all thoracic and abdominal viscera; sensory and motor
CN11
accessory; swallowing and head movement; motor
CN12
hypoglossal; swallowing and speech; motor
Reticular Activating System comprised of...
Thalamus, Hypothalamus, Amygdaloid Nuclei
Function of Reticular Activating System?
Center for arousal/alerting, associated w/ levels of consciousness; all sensory systems have some input; anesthetics act by lowering levels of consciousness.
speech area?
Broca
damage in Broca causes?
aphasia
Aphasia is?
inability to speak or write (but Broca aphasia able to understand)
around the fasciculus (bundle of neurons); PNS only
Endoneurium?
around one neuron (also called basement membrane and neurolemma); PNS only
? most numerous cell of nervous system
neuroglial
? CNS supportive cells
neuroglial cells
? microglia
doesn't exist normally in the brain; derived from mesoderm, a phagocyte, it only appears when there is a lesion in the nervous system
the CNS cannot regenerate because...
no basement membrane
? neural tube becomes
CNS
? neural crest becomes
PNS
maturation of the cerebral cortex in child development is due to...
an increase of glial cells
plasticity is...
the ability to develop new synapses and new circuits as part of the learning process
Myelination is not fully developed as an infant, therefore...
walking and developing motor skills take time
? there is no connective tissue in
CNS
? connects the cerebral cortex to the brain stem
internal capsule (strokes occur here)
if frontal lobe is destroyed...
total paralysis on opposite side of body
all conscious function is in the...
cortex
the Central Sulcus divides the...
Precentral gyrus (anterior;motor) and Postcentral gyrus (posterior, area for all sensations of the body); divides the frontal from the parietal lobes, motor vs. sensory areas
? the brain is ___ to pain
insensitive
___ is sensitive to pain
dura
CSF travel:
lateral- 3rd- cerebral aqueduct- 4th- subarachnoid space
Conus Medullaris
"V" tip of the cord
Cauda Equina
"tail" of nerves that extend past the cord
Filum Terminale
Pia anchors cord to the posterior side of coccyx
Coccygeal Ligament
Filum Terminale anchors to this
Muscle spindles
located in the muscle for reflexes (stretch) and also tells movement and speed
Joint capsule receptors
tells the position of the joints
bare (free) nerve endings
receptors for pain that respond to tissue damage
Dorsal root ganglion
cell bodies of sensory (afferent) neurons
trigeminal ganglion
cell bodies associated with sensory info for the head and neck
substantia gelantinosa
pain control for spinal pathways; gelatin substance in the posterior horn of the cord; processing center
subnucleus caudalis
pain control for cranial pathways
medial lemniscus
projection tract for the 2nd neuron for discriminating touch and proprioception; travels from medulla to thalamus
majority are these?
in CNS everywhere?
in PNS in autonomic ganglia?
mulipolar neuron
? functions for large automatic movement of skeletal muscle and muscle tone
extrapyramidal system
descending motor tracts...
Rubrospinal, Tectospinal, Vestibulospinal
Contralateral functions...
opposite sides
Sequential movements
as in writing
Substantia Nigra...
subconscious muscle activity
Striatum...
caudate and putamen
Parasympathetic
craniosacral division; functioning under "normal" conditions
CN ganglia...
cranial nerves 3,7,9, 10
Sympathetic
thoracolumbar division (T1 to L3); "flight or flight" division; major function; vasoconstriction
Chain and other ganglia...
sympathetic chain ganglion runs parallel to spinal cord
Pilomotor...
there is a muscle going to the hair making it stand on end
Secretory...
glands
Vasomotor...
blood vessels
Satellite cell?
blood brain barrier; phsycial metabolic nutrients in, waste out
Schwann cell?
produces myelin and basement membrane; neurolemma and phagocytic degenerated axons
? 3 groups of collagen fibers
epi-, peri-, endoneurium
? each fascicle surrounded by thicker collagen called
perineurium
surrounding axon?
myelin sheath
surrounding myelin sheath?
basement membrane
innermost connective tissue?
basement membrane
basement membrane secreted by?
Schwann cell
? peri- and endoneurium are ______ for stretch
wavy
? enlargement along the length of a tube (also contains NTs)
varicosity
? phagocytes
microglia
? forms multiple myelin segments
oligodendrocytes
brain grows faster than...
cranial vault (folds over itself)
? bundles of axons
nerves
? group of cell bodies
ganglia
2 areas of the spine that are enlarged...
cervical and lumbar
fiber bundles under...
gray matter
? subcortical matter
white matter
? mostly involved in strokes
middle cerebral
? drains the face, so infections can drain to meninges
cavernous sinus
associated w/ pain control in the spine:
substantia gelatinosa
associated with pain control in the cranial nerve:
subnucleus caudalis
Vestibular input?
from the semicircular canals in the ear for equilibrium
Proprioceptors input?
from the sensory component in muscles
Upper motor neuron damage causes...
spastic paralysis and increased reflexes
Lower motor neuron damage causes...
flaccid paralysis and decreased reflexes
Extrapyramidal (basal ganglia) damage causes...
tremor at rest (Parkinson's) and involuntary movements (Chorea)
Cerebellum damage includes...
ataxia (failure of muscle coordination), rebound (loss of antagonist muscle coordination), dysmetria (improper distance measuring), intention tremor (arises or intensifies when a voluntary coordinated movement is attempted)
ANS regulates...
visceral effectors (smooth and cardiac muscle, glands) to maintain or restore homeostasis
ANS is influenced by impulses from...
frontal lobe and limbic system
what releases ACh?
pre and post-ganglionic parasympathetic and pre-ganglionic sympathetic
what releases NE?
post-ganglionic sympathetic
main function of sympathetic division?
vasoconstriction
parasympathetic functions:
dominates control of most visceral effectors (smooth and cardiac muscles and glands)
? under normal conditions
parasympathetic
? under fight or flight
sympathetic
parasympathetic is associated with 4 CNs...
3, 7, 9, 10
sympathetic division or
thoracolumbar division, output travels with spinal verves t1 to l3
somatic nervous system
supplies skin and skeletal muscles
has 1 neuron between cns and the effector
somatic nervous system
has 2 neurons between cns and the effector
ans
ans supplies
effector, glands,cardiac,smooth muscles/ no skeletal muscle control
upper motor neuron involves
pyramidal neuron/cerebral cortex
lower motor neuron involves
brainstem and spinal cord
what are the 3 tracts assoc. with direct pthwy
lat corticospinal, ant corticospinal, corticobulbar
corticobulbar terminates in the nuclei of cn
3,4,,5,6,7,9-12
extrapyramidal system or ?, involved with
basal ganglia, cortical assoc with sequential movement and automatic movement, walking, laughing and muscle tone/indirect
the umn begins in the
nuclei of brain stem
corticospinal tract is completely
contralateral to the opposite trunk and limbs
pyramidal involved in
direct pthwy for precise voluntary mvmnt
equilibrium sensing
vestibular organs
proprioceptors
information of what is happening in joints and muscles (spinocerebellar tracts)
info on what movmnts are planned
cerebral cortex
saying for cn
on old olympus towering tops a fin and german viewed awesome hops
sensory/motor saying
some say marry for money but my brother says big boobs matter more
ipsilateral
cerebellar
contralateral
is cortex
conducts impulses to cord or brain
afferent,sensory
conducts impulses away from cord/brain
efferent/motor
receptor
end of sensory nerve
effector
skeletal muscle
where are most synapses
axodendritic
bipolar
1 axon, 1 dendrite, associated with special senses=vision hearing, smell vestibular/balance
multipolar
1 axon, several dendrites (most numerous)
unipolar
1 process comes off neuron, divides into axon, 1 dendrite always sensory, in pns (ex. cell bodies are in the dorsal (posterior)root ganglion of the spinal nerves)
ascending is
sensory
descending is
motor
parts of reflex
2 styles: sensory and motor
or sensory to interneuron to motor
internal carotid artery joins
the circle of willis
basilar artery
joins the circle of willis
circle of willis
located at the base of the brain (inferior aspect)
travel in the cervical vertebrae's transverse foramen and then together form the basilar artery at the base of the brain
vertebral arteries
dermatome
area innervated by specific nerve,
white matter consists of
myelinated fibers (high in fat)
gray matter is a cluster of
cell bodies
brain stem is
from the cord up/medulla oblongata, pons, midbrain
Biology Lab Midterm
