(4) nervous system [main/basic] Flashcards
functional basic unit of the nervous system
neurons
parts of the neuron structure
dendrites cell body nucleus axon myelin sheath + schwann cell + nodes of ranvier axon terminal
what do neurons make
neurotransmitters
(def) neurotransmitter
chemical messenger
what travels in the neuron
action potential
(def) action potential
electrical signal
4 nervous system tissues
neurons
nerve
ganglia
neuroglia
(def) neuroglia
neural glue
helper cell
(func) neuroglia
support & protect the neurons
maintain homeostasis in the fluid surrounding the neurons
gray matter
non-myelinated matter
beginnings and ends of neurons
edges of the brain
white matter
myelinated matter
axons of neurons
connects gray matter to each other
resting potential
neuron at rest - not firing/no signal transmission
stimulus
causes a change in ion charge across the neuron membrane
action potential
minimum threshold of charge across the membrane reached - all or nothing firing
refractory period
period of time before the membrane returns to resting potential
5 neurotransmitters
epinephrine dopamine endorphins serotonin acetylcholine
2 types of neurotransmitter mimics
agonists (excitatory)
antagonists (inhibitory)
agonists (excitatory)
stimulants
increase neurotransmitter effects
ex. nicotine, caffeine, cocaine, amphetamines
antagonists (inhibitory)
depressants
slow neurotransmitter effects
ex. botox, alcohol, heroin, oxycodone
2 main divisions of the nervous system
central (CNS)
peripheral (PNS)
parts of the CNS
brain, spinal cord
parts of the PNS
nerves
main functions of the brain
homeostatic center data integration analyze info intellect/reasoning emotions
main function of the spinal cord
relay info and responses between the brain and PNS
the CNS is eclosed in
bone
meninges
cerebral spinal fluid
other: blood-brain barrier, ventricles
(def) ventricle
hollow spaces within the brain filled with cerebral spinal fluid
(def) cerebral spinal fluid
circulating fluid that surrounds the brain & spinal cord
(func) cerebral spinal fluid
cushion
protect
keep surfaces moist
4 parts of the WHOLE brain
cerebrum
cerebellum
diencephalon
brain stem
brain weighs
3 lbs
(func) cerebrum
higher brain functions reasoning thought emotions senses process sensory info
(func) cerebellum
involuntary movement of muscle fibers
coordination
posture
balance
(func) diencephalon
homeostasis hunger sleep temperature water balance
(func) brain stem
relay station between the cerebrum, cerebellum, and the spinal cord
regulating heart and respiratory functions
affects consciousness
sleep cycle regulation
(func) corpus callosum
connects the brain’s left and right hemispheres
human body (brain power)
pushing the limits
how the brain makes time run slower
processes more in less time
ex. 50 snaps per minute becomes 100 snaps per 30 seconds
how people enjoy eating unappetizing/painful foods
instinctual drives to obtain the nutrients we need
in terms of spicy foods: they send pain signals to the brain, then the brain releases endorphins. this gives a pleasurable sensation so we remember this later on
chocolate & kissing affect the
the pleasure center
how the brain changes the body during starvation
1 - drive to find food: chemical released to enhance muscles/high alert/sharpen problem solving
2 - survival: slow down to use less energy (muscles and organs), new cells grow slowly, unnecessary cells scarcely grow (hair and nails)
3 - eat itself: destroying protein (muscles)
how the brain stays cool
sweating: blood carrries heat to the skin’s surface, sweat evaporates, blood cools, cools brain
how the brain puts us to sleep
releases melatonin
side-effects of not sleeping
not being at peak performance
irrational/poor decision making (frontal lobe)
imagining things/disorientation
brain shuts off, no matter the outcome
the sensory process that stays on during sleep
hearing - temporal lobe
chemicals clean the byproducts of daily cell activity
what part of the brain shuts down during sleep
frontal lobe: logic center
brain cells that worked throughout the day
the reason we cannot move while dreaming
brain sends signals to the spinal cord, temporary paralyzing us
lucid dreaming
“harnessing the sleeping brain’s power”
realizing you’re in a dream without waking and choosing what happens in the dream
negative outcomes if we don’t dream
not filling away the information we learned throughout the day
not consolidating knowledge/memories
less imaginative
