day 10 - neuro Flashcards
PNS is split into BLANK and BLANK systems
PNS is split into SENSORY and MOTOR systems
motor division of the PNS is split into BLANK and BLANK
somatic (skelital muscles) and autonomic (involuntary)
autonomic division of the PNS is split into BLANK and BLANK
sypathetic and parasympathetic
hormone (def)
chemical released into the blood
autonomic nervous system (func)
controls internal environment by sending signals to effector organs
works closely w/endocrine system (neuroendocrine system)
dendrite
carries signals TO the soma/cell body of neuron
axon
carries signals AWAY from the soma/cell body of neuron
1 neuron controls around BLANK muscle cells
1 neuron controls around 1000 muscle cells
how many neurons from spinal chord to target in somatic motor + sensory signals
1 neuron from spinal chord to target
how many neurons from spinal chord to target in autonomic (smooth muscle, cardiac muscle, glands, etc) signals
two neurons:
spinal chord to synapse (primary neuron)
synapse to target (secondary neuron)
arteries have BLANK muscle surrounding them
smooth muscle
can blood vessels make themselves larger?
vessels CANNOT make themselves bigger, the smooth muscle surrounding them relaxes
reaching a neuron’s threshold is caused by the BLANK of excitatory and inhibitory signals
SUMMATION of excitatory and inhibitory signals
proprioceptors (def)
provide CNS with sensory info about body position + movement
mechanoreceptors (3 types)
muscle spindles, golgi tendon organs, free nerve endings
chemoreceptors (def)
provide CNS with info regarding the metabolic rate + muscle activity
baroreceptors (def)
provide CNS with info about pressure (ex. blood pressure in vessels)
reflex (def)
rapid, unconscious reaction to stimulus
muscle spindles (shape)
shaped like a spring (compresses + uncompresses)
muscle spindles (func)
detect changes in muscle length + how fast it is getting longer/shorter
what reflex are muscle spindles responsible for
knee-jerk reflex
special muscle fibers name
intrafusal fibers
intrafusal fibers
special muscle fibers
explain the muscle action in the knee-jerk reflex
a rapid stretch causes a reflex contration or shortening of adjacent muscle fibers
muscle spindle sense stimulus (knee hit) and tells brain something moved BUT you didnt tell it too, protection = contraction
motor unit (def)
a single motor neuron and all the fibers it inervates
innervation ratio (def)
number of muscle cells per motor neuron
ex. 1:10 in eye vs 1:1000 in leg
cerebellum (func)
coordinates/figures out how to get plan done (plan comes from motor cortex)
motor neurons in PNS carry messages from BLANk to BLANK
from spinal chord ganglia to skelital muscles
golgi tendon organs tell CNS…
how much tensions is being produced by entire muscle
golgi tendon organs protect us from BLANK
protect us from recruiting too many muscle fibers (too strong for our own good)
wont let you produce too much tension
autonomic nervous system (func) + what it controls
assists in maintaining internal environment (involuntary)
controls: smooth muscle, cardiac muscle, glands
is SYMPATHETIC “fight or flight” or “rest and digest”
SYMPATHETIC is fight or flight
is PARASYMPATHETIC “fight or flight” or “rest and digest”
PARASYMPATHETIC is rest and digest
is sympathetic ususally excitatory or inhibitory
excitatory
is parasympathetic ususally excitatory or inhibitory
inhibitory
sympathetic is in what devision(s) of the spinal chord
thoracic + lumbar regions of spinal chord
parasympathetic is in what devision(s) of the spinal chord
cervicle + sacral regions of spinal chord
in SYMPATHETIC system, presynaptic neuron releases BLANK onto postsynaptic neuron which releases BLANK (excitatory/inhibitory)
presynaptic neuron: releases ACh
postsynaptic neuron: releases norepinephrine (+)
in PARASYMPATHETIC system, presynaptic neuron releases BLANK onto postsynaptic neuron which releases BLANK (excitatory/inhibitory)
presynaptic neuron: releases ACh
postsynaptic neuron: releases ACh (-)
