basics 1 Flashcards
What makes up the nervous system (7)
brain 12 pairs of cranial nerves + branches spinal cord 31 pairs of spinal nerves + branches ganglia enteric plexus sensory receptors
3 types of neurons based on their function
sensory (afferent)
interneuron
motor (efferent)
CNS made up of
brain
spinal cord
PNS made up of
cranial nerves
spinal nerves
ganglia
sensory nerves
sensory nerves also called
afferent
motor nerves also called
efferent
PNS is also then subdivided into…
somatic nervous system
autonomic NS
enteric NS
The SNS made up of/does what
1) neurons that conduct impulses from somatic and special sensory receptors to the CNS
2) motor neurons from from CNS to skeletal muscle
ANS consists of
sensory neurons from visceral organs, motor neurons from CNS to smooth, cardiac muscle & glands
ENS consists of
2 plexuses that control GI
monitors sensory changes and controls operations
resting membrane potential of neutron
- 70mV
what forms myelin sheaths
oligodendrocytes
what forms blood brain barrier
astrocytes
what has phagocytic functions in NS
microglia
autonomic NS innervates what
visceral structures (maintains homestasis)
grey matter is rich in
cell bodies
white matter is in
axons
cluster of cell bodies with similar functions are called?
nuclei
what word means “crosses over”
decussates
which germ layer gives rise to nervous system
ectoderm (also skin)
embryology progression to neural tube
ectoderm > neural plate > neural grove with neural fold > neural folds fuse to form neural tube
where do you find grey matter
centre of spinal cord and outer regions of brain (cerebral cortex)
forebrain called
prosencephalon
midbrain called
mesencephalon
hindbrain called
rhombencephalon
(embryology) the prosencephalon divides into
telencephalon and diencephalon
(embryology) rhombencephalon divides into
metencephalon and myelencephalon
forebrain also referred to as the
cerebrum
3 meningeal layers
dura mater
arachnoid mater
pia mater
2 sheets of cranial dura mater
falx cerebri
tentorium cerebelli
- these incompletely divide cranial cavity into compartments
what has channels for venous drainage of the brain
dural venous sinuses of the cranial dura mater
what is located below arachnid mater
subarachnoid space where CSF circulates
what supplies blood to brain
internal carotids and vertebral arteries (anastomose to form circle of willis)
what supplies blood to the spinal cord
vessels arising from vertebral arteries and radicular arteries derived from segmental vessels
meningeal layers from superficial to deep
dura > arachnoid > pia
subarachnoid space located where
between arachnoid and pia mater
most significant blood supply to intercranial meninges
middle meningeal artery
dorsal roots carry
afferent signals
ventral roots carry
efferent v’E’ntral
dorsal root cell bodies are located where
dorsal root ganglion
ventral root cell bodies are located where
in spinal grey matter
spinal nerves leave vertebral canal through
intervertebral foramina
at what level does spinal cord end
between L1 and L2
H shape in spinal cord called
central canal (with dorsal and ventral horns)
what occurs at dorsal horns
termination of afferent neurons and origin of ascending pathways
only where do you find the lateral horn
thoracic and upper lumbar cord
lateral horn is made up of?
cell bodies of preganglionic neutrons belonging to the sympathetic division of the autonomic NS
what is found in white matter
ascending and descending tracts
ascending tracts include
dorsal columns
spinocerebrellar tracts
spinothalmic tracts
descending tracts include
lateral corticospinal tracts
