Studied by 3 people
neuron
nerve cell
dendril
fibers that receive information
axon
fibers that send info to other neurons, muscles, and glands (very long)
myelin sheath
fatty tissue which insulates axon and helps speed up impulses; multiple sclerosis is when it deteriorates
impulses
travel between 2 to 200 mph
cell body
mitochondria turns glucose into energy for cell life support
action potential
electrical charge that travels down an axon
ions
electrically charged atoms
polarized
resting axon is more negative on the inside and more positive on the outside
selectively permeable
axon is selective about what it allows in
depolarization
gates open along axon and allow positive ions to flow in (Na+)
threshold
the level of stimulation required to trigger a neural impulse
self-propogating
one part depolarizes causing the next channel to open (like falling dominoes)
all or none
a neuron either fires completely or does not fire at all
refractory period
after firing, the neuron must recharge. positive potassium (K+) flows out and the neuron becomes repolarized. this process occurs up to 1000 times per sec
neural communication synapse
gap between the neurons
axon terminals
contain vesicles/sacs which release chemicals across the gap
neurotransmitters
chemicals that cross the synapse and bind with receptors on dendrites of the next neuron
reuptake
excess neurotransmitters are reabsorbed back into the vesicles
agonist
acts like the neurotransmitter and binds with the receptor (tricks brain)
antagonist
blocks receptor so that neurotransmitter can't stimulate receptor or may inhibit release of neurotransmitter (like ibuprofen)
lock and key
neurotransmitters have a certain shape, only fit with certain dendrites
blood brain barrier
brain screens out unwanted chemicals circulating in the blood; dopamine won't cross the barrier but L-Dopa (agonist) will (used for Parkinson's)
neural networks
clusters of neurons working together to accomplish the same task (work as a group)
afferent
bring pain inward, sensory
efferent
reflex, pain signal sent to spine, makes one synapse around spine/nerve, goes back to hand/where it occurre, when pain is bad, bring pains outward, motor
chemicals used in depolarizing process
sodium, calcium, potassium
order energy travels
dendrite, cell body, axon
excitatory
tells rest to fire
inhibatory
goes across synapse into lock and key, tells not to fire
central nervous system
incased in bone, brain and spinal cord
peripheral nervous system
outside bone
somatic
motor and sensory, efferent and afferent
motor
nerves that allow you to move
sensory
5 senses
autonomic
controls all things in the body you don't have to think about
sympathetic
turns on fight or flight
parasympathetic
turns off fight or flight
Note 
Flashcard (71)