 | Term | Definition |
| |
cns |
brain, spinal cord |
| |
pns |
cranial nerves, spinal nerves |
| |
sympathetic |
fight or flight |
| |
parasympathetic |
rest & digest "housekeeping" |
| |
astrocytes |
cns-- blood-brain barrier |
| |
microglia |
phagocytes |
| |
ependymal cells |
csf formation |
| |
oligodendrocytes |
myelin sheath |
| |
schwann cells |
pns--myelin sheath |
| |
satellite cells |
pns--cushioning protection |
| |
perikaryon |
(soma) most in cns--nuclei, few clusters in pns--ganglia |
| |
dendrites |
receptive/input region, short, highly branched, oraganelles present |
| |
axons |
one/neuron, arise from axon hillock, account for neuron length |
| |
myelin |
fatty insulation material,conduct impulses faster, insulate axons |
| |
nodes of ranvier |
between schwann ,cout layer cytoplasm &cell nucleus-neurilemma |
| |
neurilemma |
pig in a blanket |
| |
white matter |
myelinated fibers, cns--tracts; pns--nerves |
| |
gray matter |
unmyelinated, cns--nuclei; pns--ganglia |
| |
multipolar |
several dendrites one axon |
| |
bipolar |
one dendrite one axon |
| |
unipolar |
one axon and one dendrite fused together |
| |
motor or efferent neurons |
carry impluses away from cns to the effector organs(muscle/glands) |
| |
action potential |
electrical energy (neurons have to have) |
| |
Na+, K+ |
gates specific for an ion |
| |
resting membrane potential |
clustering of oins on cell membrane allows for this |
| |
+ ions |
cluster outside |
| |
excitable cells |
communicate by changing membrane potentials muscle cells & neurons |
| |
-70mV |
polarized rmp for neutrons ( at rest) |
| |
depolarization |
reduction of membrane potential (more + than -) |
| |
hyperpolarization |
increase of membrane potential (more - than +) |
| |
repolarization |
back to rest |
| |
graded potential |
short-lived, local membrane disturbance |
| |
55mV |
local currents open voltage regulated Na+ gates |
| |
all or none |
reach threshold-get potential; stimulus strength not a factor |
| |
strong stimuli |
nerve impulses generate more freq; difference in perception |
| |
faster |
large axon diameter; myelinated axons |
| |
multiple sclerosis |
autoimmune, loss of myelin, loss of vision, info goes both ways |
| |
group a |
large myelinated; somatic sensory and motor neurons; are quick |
| |
group b |
lightly myelinated, intermediate; in autonomic system |
| |
group c |
small, unmyelinated; in autonomic system |
| |
synapse |
junction between neurons & another cell (neuron, muscle, gland) |
| |
most common synapse |
axodendritic to axosomatic |
| |
less common synapse |
axoaxonic, dendrodendritic, dendrosomatic; poorly understood |
| |
electrical synapse |
occur in brain, rapid communcate-both ways, synchronize activities |
| |
chemical synapse |
neurotransmitters,alter membrane permeability,most only go 1 way |
| |
diverging |
neural integration: 1 incoming signal triggers multiple signals |
| |
converging |
neural integration: multiple signals pooled to 1 output signal |
| |
reverberating/oscillating circuit |
incoming signal feeds back to neurons in pathway |
| |
parallel after discharge circuit |
incoming signal stimulates parallel circuits-timing of output |
| |
serial processing |
input along single pagthway to specific destination (dr. + hammer) |
| |
neuroblastoma |
malignant tumor in children |
| |
neurologist |
studies nervous systems |
| |
neuropathy |
any disease of nervous tissue |
| |
neuropharmacology |
study of the effects of drugs on nervous system |
| |
neurotoxin |
substance poisonous to nervous tissue; botulism,tetanus, venoms |
| |
rabies |
viral infection of ns of humans from bites of infected animals |
| |
shingles |
herpes zoster;viral infection of sensory neurons of skin |
| |
botulisim |
botox, state of relaxation |
