anatomy nervous system test Flashcards
what is the central nervous system composed of?
brain
spinal cord
What is the peripheral nervous system composed of?
all neural tissue outside the central nervous system
what type of neuron is located between sensory and motor neurons (in brain and spinal cord)
analyze inputs, coordinates outputs
roles in memory, learning and planning
interneurons
which kind of neuron delivers signals to muscles/organs
stimulate or inhibit peripheral tissues
efferent division
motor neuron
which type of neuron monitors internal+external environments
deliver information to the central nervous system
afferent division
sensory neurons
support framework for neurons
neuroglia
transfer, process, and store information
neurons
maintain the blood-brain barrier
largest and most numerous
astrocytes
create myelin sheath around neurons
lining of brain and spinal cord activities
oligodendrocytes
defense and disposal of debris
smallest and rarest neuralgia
microglia
circulate cerebrospinal fluid
ependymal cells
describe how action potential gets sent
- membrane @ -70mV on the inside (resting potential)
- stimulus occurs, sodium rushes in, membrane changes to +30 mV (Depolarization)
- potassium leaves the cell until returns to -80 mV (repolarization)
- sodium/potassium pump brings ions back to normal (Salty banana)
- refractory period (no new stimulus)
sodium: outside or inside
outside
potassium: outside or inside
inside
axon is unmyelinated, action potential through the whole membrane
continuous propagation
axon is myelinated, action potetential only on the nodes of rarivor
saltatory
which neural pool: several neurons send information to one other
example: consciously controlling breathing
convergent
which neural pool: spread information from one neuron to several others (many different responses to an event)
example: stepping on a tack
divergent
outside layer
Tough fibrous outer layer
dural folds hold the brain in position
connects to skull
dura mater
space filled with cerebrospinal fluid for shock absorption
middle layer
“Spidery”
arachnoid
Connects to brain
inside layer
highly vascular
pia mater
function of the spinal cord
relays information to/from the brain and processes some information on its own
describe the structure of a spinal nerve
combo of sensory (dorsal) and motor (ventral) in one nerve
what structure makes cerebrospinal fluid
chord plexus
which lobe: emotion control, decision making, executive functions
frontal lobe
which lobe: sensory input, memories
parietal
which lobe: vision
occipital
which lobe: language, hearing, memory, speech
temporal
controls breathing, heart rate, and blood pressure, and acts as a relay between the brain and spinal cord.
brain stem
balance, muscle memory, motion memory, body control
cerebellum
directs voluntary movement, responds to sensory information–> motor
precentral gyrus
receives somatic sensation (touch, pain, pressure, temperature
postcentral gyrus
sorts data
thalamus
homeostasis, temperature
hypothalamus
connects the right and left hemispheres
corpus callosum
describe how a signal is sent (when you step on something) from your toe, up to your brain and back down to your leg muscle. Include the specific parts the message will run thru.
Stepping on something: stimulus
sensory pathway thru sensory neurons (carry pain signal from site of injury to brain.
interneurons make decision on the reaction
sent to the brain back thru the motor nerves that sends a response through to the leg for the reaction
“fight or flight”
sympathetic division
example of sympathetic division situations and how they effect 3 organs
car accident, fight
-heart rate increases, lungs: increased breathing rate, pupil dilation, start to sweat
“rest and digest”
parasympathetic
example of parasympathetic division situations and how they effect 3 organs
beach, sleep, yoga (anything relaxing)
- decreased heart rate, slower breathing, pupil constriction
increased alertness, euphoria + energy, increased cardiovascular, increased respiratory activity, increased muscle tone
sympathetic
relaxation, food processing, energy absorption
parasympathetic
how does the nervous system change with age ?
loss of neurons
changes in synaptic organization of the brain
intra and extra cellular changes in central nervous system neurons
reduction in brain size and weight
decrease in brain blood flow
