Lecture Outline #13: CNS Flashcards
functions of ns
awareness
coordination & control
memory & learning
establishing patterns of response
CNS
brain & spinal cord
PNS nerves
cranial (motor & sensory) & spinal (motor & sensory) (controls skeletal muscle contractions and voluntary/involuntary reflexes) nerves.
PNS subsections
sensory - visceral (organ information) and somatic (info from body)
motor - ANS and somatic (skeletal muscle (voluntary))
ANS componants
involuntary visceral - smooth & cardiac muscle
ANS subsections
sympathetic (thoracolumbar) & parasympathetic (craniosacral)
ANS sympathetic function
speeds heart & slows GI tract
“fight or flight” response, adrenaline
ANS parasympathetic function
slows heart & speeds GI tract
“rest & digest” involuntary control
controls smooth muscle contractions (gut & vasculature)
soma
cell body
contains nucleus & mitochondria
most lack centrioles (can’t divide)
soma - hilum
proximal stump where nerves regenerate
dendrites
receive input from environment or other cells
axon
conducts nerve impulse
hollow extension of soma - cytoplasm
insulated by myelin sheath
synaptic terminals
output to muscle/gland/nerve
3 targets for synaptic terminals
- synapses with other neurons
- neuro-muscular synapses (control)
- neuro-glandular synapses (no control)
structural type of neuron - anaxonic (CNS)
dendrites/axons look alike, no axons
brain & ganglia (processing centers)
structural type of neuron - bipolar
soma is situated btw dendrite & axon
special sensory cells - sight, smell, hearing
structural type of neuron - unipolar
soma is situated on one side of dendrite & axon
sensory nerve endings of the PNS
structural type of neuron - multipolar
several dendrites & single axon
common in CNS, motor nerves, skeletal muscle