Chapter 14 Flashcards
spinal cord is a link between
brain and rest of body
responses that do not involve the brain are called
spinal reflexes
spinal cord runs from brains medulla through
vertebral canal
inferior end of spinal cord rapers to form
conus medullaris
adult spinal cord is normally ____ inch diameter. and ______ length
3/4; 16-18 inches
the spinal cord is shorter then the
vertebral column
longitudinal depressions are
posterior median sulcus
and anterior medan fissure
4 main porions of spinal cord
cervical, thoracic, lumbar, sacral
two widened regions with greater
cervical enlargment and lumbar enlargment
in cervical enlargement the neurons innervate
upper limbs
in lumbar enlargement neurons innervate
lower limbs
nerve is a
cablelike bundle of axons
how many spinal nerves are there
31
regions of spine in order top to bottom
cervical, thoracic, lumbar, sacral
epineurium
around nerve
perineurium
around fascicle
posterior root ganglion
contains cell bodies of these neurons
rootlets merge to form
roots
posterior root contains
sensory neurons
anterior root contains
motor neurons
spinal nerves have both
sensory and motor neurons
mixed nerves
has motor and sensory neurons
spinal nerves are considered ______ nerves
mixed
cauda equina means
horse tail
posterior horn is ______ part of butterfly
thin
roots form structure called
cauda equina
grouping of nerves called
plexi
what houses spinal cord
vertebral column
spinal cord protected by
bone, meninges, CSF
spinal cor passes through
vertebral canal
each spinal nerve exits through an
intervertebral foramen
spinal cord meninges
pia mater, arachnoid mater, dura mater
in spinal cord we have horns that make up
gray matter
gray matter sits in _____ of spoinal cord
center
posterior horns
house axons sensory neurons
lateral horn houses
automatic motor neurons
anterior horns house
cell bodies of somatic motor neurons
in between horns is called
gray commisure
_______ is hole in middle of spinal cord that allows cerbral spinal fluid to flow through
gray commisure
motor neurons are found in
anterior and lateral neurons
sensory neurons in spinal cord are in
posterior horn
somatic motor nuclei innervate
skeletal muscle
somatic motor nuclei is ___ control
conscious
autonamtic motor nuclei innervates
heart and other glands
dermatomes
segment of skin supplied by single spinal nerve
sometimes when we have damage to internal organs we can manifest sensation on skin. this is called
referred visceral pain
example of referred visceral pain
heart feels pain. people would heart attack might complain about pain in heart but more often they will complai about pain in body.
nerve plexus grouping how many
4 main nerve plexus
what are the 4 main plexus
cervical plexus, lumbar plexus, sacral plexus, brachial plexus
cervical plexuses innervates
interior neck muscles, skin of neck, portions of head and shoulders
what comes off of plexus’s
terminal branches
how many terminal branches are there.
5 main ones
what are the 5 major terminal branches in brachial plexus
auxillary, median, musculocutaneous, radial, ulnar
brachial plexus has to do with branches to
arm
auxillary nerve in brachial plexus
median nerve in brachial plexus
to deltoid, major muscles, sensory input grm superlateral arm
musculocutaneous nerve in brachial plexus
most anterior forearm muscles
radial nerve in brachial plexus
posterior arms muscles.
ulnar nerve in brachial plexus
anterior forearm muscles.
lumbar plexus has to do with
lower back
how many nerves are associated with lumbar plexus
- femoral nerve, obuturator nerve
femoral nerve goes to
femur and thigh
obuturator nerve goes to
thigh
sacral plexus has 2 nerves
tibial nerve, common fibular nerve, sciatic nerve
tibial nerve of sacral plexus
innervates hamstring part of adductor magnus
sciatic nerve of sacral plexus
breaks down into 2 divisions tibial and fibular nerves
common fibular nerve innervates
short head of biceps femoris msucle
largets and longest nerve in body
sciatic nerve
fibular nerve branches out into
deep fibular nerve and superficial fibular nerve
characteristics of reflexes
stimulis is required to inititatie reflex
response is rapid involves chain of only a few neurons
response is preprogrammed;always the same
response is involuntary; no intetent or awareness of reflex before occurs
reflexes
rapid, reprogrammed, involuntary responses of muscles of glands to a stimulus
reflexes are _____ mechanisms
survival
reflex arc
neural pathway responsible for generating the response
reflex how it happens
stimulis received
nerve signal is programmed through senseoty neurons to the spinal cord
nerve signal is processed in the integration center by interneurons
nerve signal is propogated by motor neuron to effector
effector responds