Nervous System Flashcards
Exam 2
application of NS
sensations
movement
proprioception
posture
balance
involuntary living activities
parts of a neuron
dendrite, cell body, axon, nerve endings
anotomical divisions of NS
peripheral and central
functional divisions of NS
autonomic and somatic
sympathetic is what
fight/flight
parasympathetic is what
calmin rest and digest
afferent neurons
sensory. to central
Efferent neurons
motor. to peripheral
at rest what is na and k concentrations of cell
na outiside and k inside
what part of a cell is excitable
the cell membrane
what changes in response to stimul
electrical potentail
each neuron recives stimuli from what
many neurons at dendrite
excitatory def
increase in the electrical potential of cell membrane
brin neuron closer to threshold
inhibitory def
decrease in the electrial potential of cell membrane and brings neuron farther fro threshold
3 types of receptors
mechano
thermo
chemo
what happens if a neuron maintains membrane potential below the threshold level
neuron does NOT generate an AP
what happens if the increase in mebrane potential is above a threshold level
the neuron depolarizes and an AP is generated
what happens after an AP is generated
it propagates down the azon to terminal endings to stiulate (other dendrites is a sensory neuron and muscle fibers if a motor neuron
kinestetic responds to what
respond to acceleration
vestibular receptors respond to what
change in body position and change fluid in ears.
what is an interneuron between
an afferent and efferent neuron
what are the 5 reflexes
spinal reflex
myotatic (stretch) reflex
flexion reflex
reciprocal inhibition
crossed extensor reflex
of nueonrs involved in spinal reflex.
myotatic (stretch) reflex,
flexion reflex
spinal reflex is min of 2
myotatic (stretch) reflex is 2
flexion reflex is 3
where is a muscle spindle found
on the belly of muscle
what does a muscle spindle respond to
change in length
where is a golgi tendon located
on the tendon
what does a goldi tendon organ respond to
tension
steps of golgi tendon relex steps
- golgi tendon senses excessive tension
- sensory neuron conducts AP
- sensory neurons synapse with interneurons
- alpha motor neuron to quadricept is inhibited while the alpha motor neuron to the hamstring is stimulated
- the hamstring contracts and the quadricept relax
what do free nerve endings located distally on a limb communicate with
motor neurons to the limb flexor muscles
what is the withdrawal effect and examples
free nerve endigns are sitmulated by contact with so say a hot surface or foot on sharp object
purpose of withdrawal effect
to protect from injury
what does the crossed extensor relex combine
the flexor withdrawla dn extensor thrust reflexes
what is the crossed extensor reflex initiated by
pain in supporting limb.
crossed extensor reflex broken down
flexor withdrawl reflex on supporting leg. extensor thrust reflex on opp leg. support shifted from irritated limb to opposite limb
