nervous system book Flashcards
the peripheral nervous system is made of what
the nerve fivers and the cell bodies outside the CNS that conduct impulses to or away from CNS
The central nervous system is made of what
brain and spinal cord
the somatic nervous system is for what
voluntary sensation, afferent toward the CNS
automatic nervous system does what
involuntary visceral nervous system that carries impulses from the CNS efferent
neurons are what
nerve cells functional units of the nervous system
a neuron is composed of
a cell body
dendrites (extensions)
axon
dendrites carry impulses _____ the cell body
toward
axons carry impulses ______ away from the cell body
away
myelin
layers of lipid and protein
increases speed of impulses
neuroglia
glial cells or glia
support, insulate, and nourish neurons
nonexcitable cells
nucleus
collection of neural cells in the CNS
tract
bundle of nerve fibers (axons) connecting nuclei of the CNS
gray matter
cell bodies of nerves are here
white matter
interconnecting fiber tract systems
gray horns
posterior and anterior
3 layers of membrane that constitute the meninges
pia mater
arachnoid mater
dura mater
pia mater
innermost layer
csf located
between the pia mater and the arachnoid mater in the subarachnoid space
epidural space
fat filled area that seperates the dura mater from the spinal cord
astrocytes
glial cells that stop the regeneration of the nervous tissue
peripheral nerves consist of
bundles of nerve fibers, their connective tissue coverings, and their blood vessels
a nerve fiber consists of
axon
neurolemma
cell membrane of schwann cells
endoneurium
myelinated nerve fibers
myelin sheath wrapped single axon
unmyelinated
multiple axons
most skin neurons
nerve coverings
endoneurium
perineurium
epineurium
perineurium
dense CT
epineurium
thick CT includes fatty tissues blood vessels and lymphatics
ganglion
collection of nerve cell bodies outside the CNS
peripheral nerves are either ____ or ______
cranial or spinal
there are ____ pairs of cranial nerves
12
____ of the ____ number of cranial nerves arises from the brain
11 of 12
CN XI arises from
superior part of the spinal cord
all CNs exit the cranial cavity through the
foramina in the cranium
there are ___ pairs of spinal nerves
31
number of spinal nerves per region cervical \_\_\_ Thoracic\_\_\_ lumbar\_\_\_\_ sacral\_\_\_ coccygeal\_\_\_\_
8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal
spinal nerves arise from
nerve rootlets
nerve rootlets join to form
nerve roots
the anterior root consists of _______ fibers
motor ( efferent)
posterior roots are ___
afferent sensory
posterior rami
supply nerves to synovial joints of the vertebral column, deep muscles of the back, and overlying skin
the anterior rami
supply nerves to the anterior and lateral regions of the trunk and the upper and lower limbs
sympatheic (thoracolumbar) nervous system does what
catabolic reactions that prepare your fight or flight
parasympathetic (craniosacral) nervous system does what
anabolic reactions that conserve energy
the presynaptic neuron is located where
the gray matter of the CNS
the second neurons ( the postsynaptic ) neurons are where
the autonomic ganglia outside the CNS
the sympathetic division releases what neurotransmitters
norepinephrine
the parasympathetic division releases what neurotransmitter
acetylcholine
the superior cervical ganglion of each sympathetic trunk lies at the base of what
the cranium
the ____ forms inferior where the two trunks unite at the level of the ____
ganglion impar, coccyx
white rami communicantes
all the presynaptic sympathetic fibers leave the anterior rami of the spinal nerves through this to the sympathetic trunk.
