basic NS Flashcards
CNS
brain, cerebellum, brainstem, spinal cord
PNS
nerves outside cerebrum, brainstem, spinal cord
cranial nerve VII (the facial nerve) is part of which NS?
PNS
name the 7 aspects/parts of a neuron
-dendrites
-soma
-axon
-myelin sheath
-nodes of Ranvier
-terminal
-synapse
types of neurons (3)
motor neuron, sensory neuron, interneuron
function and role of motor neuron?
transmit signals from CNS to muscles; movement (voluntary & involuntary actions)
function and role of sensory neuron?
transmit sensory info from sensory organs to CNS; external stimuli to internal electrical impulses
function and role of interneuron?
communicate within CNS; sensory inputs & motor outputs; reflexes, neuronal oscillations, neurogenesis
why is the myelin sheath important?
speeds up transmission of electric impulses along axons by allowing saltatory conduction
the majority of the brain is ?
white matter
axon terminal function?
to release NTs into the synapse
gray matter function?
muscle control, sensory perception,
memory, emotions, speech, decision making, etc.
white matter function?
connects brain regions; facilitates quick transmission of nerve signals
the process by which neurons send and receive signals is called?
neural impulse transmission
neural impulse transmission steps (5)
- resting potential
- depolarization (rising)
- repolarization (falling)
- hyperpolarization
- resting potential (refractory period)
what channel is active during the depolarization phase?
sodium channels open to let sodium ions in
what channel is active during the repolarization phase?
potassium channels open to let potassium ions out
what happens during restoration phase?
sodium-potassium pump makes both types of ions switch back to resting phase positions
what cannot happen during a short period during the hyperpolarization phase?
no new action potential can be initiated
during the initial resting phase, which ions are outside and which are inside?
potassium ions are inside, sodium ions are outside
what is the initial mV of the neural impulse transmission sequence?
-70mV
what is typically the peak voltage during a neural impulse transmission sequence?
30/40mV
