nervous system 11.1 Flashcards
2 components of CNS
brain + spinal cord
2 pathways in PNS
sensory pathways and motor pathways
2 components in motor pathway
somatic (voluntary) and autonomic (involuntary)
2 components of autonomic pathway
sympathetic (fight/flight) ad parasympathetic (rest and digest)
pathway of impulse
sensory receptor- sensory neuron- interneuon- motor neuron- muscle/effector
dendrites
receive info form axons and carry impulses to cell body
cell body
recieves input from dendrites and relays it to axons
axons
carry impulses away from cell body
axons terminals
release NT to receptors of dendrites of other neurons
myelin sheath
insulator preventing the loss of ions and speeding up nerve impulses
nodes of ranvier
unmyelinated gaps in myelin sheath
impulses jump from one node to the next
white matter
myelinated axons
grey matter
unmyelinated axons
reflex arc
involuntary response to stimuli that happens before the brains aware of what’s happening
describe synaptic tranismission
generally- Ca flood in, NT go to edge of presynaptic membrane and through exocytosis enter the synaptic cleft. NT diffues through cleft and onto the post synaptic protein receptors changing the membranes permiabilty to Na
Na/K exchange pump uses ___
ATP to transport 3 Na ot of cell and 2k in
AP occurs at ___
nodes of ranvier in myelinated neurons
-70__ -50 has ____ effect
no effect on depolarization
NT can be ___ or ____
excitatory or inhibitory
gap between neuron-=
synaptic cleft
threshold =
-55mv depolarizing to 35mv
resting membrane potention =
70 MV
nerve impulse travels
dendrites-cell body-axons- axon terminals
4 parts of a nerve impulse
1)resting membrane potential
2) depolarization
3)repolarization
4)refractory period
