Physiology Part 1 Flashcards
Ascending phase, influx of sodium
Depolarization
Descending phase, efflux of potassium
Repolarization
-90 mV
resting state (membrane polarized)
permeable to sodium ions
what stage
depolarization stage
Rapid diffusion of potassium to the exterior
Repolarization stage
Two gates of voltage gated sodium channel
activation and inactivation gates
T/F: Inactivation gate will not re-open until membrane potential is at or nearly at “resting membrane potential” level.
True
Term for most synapses (axon to dendrite)
axodendritic
Tunnels which connect cytosol of two cells for synaptic transmission
Gap junctions (connexons)
Do chemical synapses touch?
no, very close though
What is myelin made of?
fat
What are the 3 excitatory neurotransmitters?
Norepinephrine,
Glutamate,
Nitric Oxide
(eNGiNes excite me)
What are the inhibitory neurotransmitters?
Glycine, GABA, Serotonin, AcH, Dopamine
GG SAD
What do MS, PLS, and ALS all have in common?
Demyelinating diseases
Which has more presynaptic bulbs, spatial or temporal summation?
spatial (takes up more space)
temporal summation only has 1
pupil constriction
miosis
areas of greatest number of pain nociceptors
tip of tongue, lips, genitals, finger tips
encapsulated mechanoreceptors assessing pressure
end bulbs of KRAUSE
encapsulated mechanoreceptor,
multi-branched,
perception of temp and pressure
corpuscles of RUFFINI
Iggo Dome Receptors, not encapsulated, anterior spinothalamic tract, hair follicles, general touch
Merkel’s discs
encapsulated fine touch receptors on non-hairy skin
meissner’s
phasic receptor
quick adaptor
pressure, vibration
encapsulated
Pacinian Corpuscles
Receptors that are not encapsulated
Merkel’s discs
Proprioception receptors
muscle spindels, Golgi Tendon Organs, and Golgi Tendon Reflex
Prevents excessive tension in a muscle
Golgi Tendon Reflex
Which has cholinergic receptors, sympathetic or parasym?
parasym (sym has adrenergic)
Absolute refractory
no action potential possible
Relative refractory
action potential available with increase potential
many synapses in a single cell
spatial summation
rapid succession of action potential, few synapses
temporal summation
these cells normally release glycine, preventing excessive muscular contraction but their respective glycine receptors are blocked during strychnine poisoning.
Renshaw cells
What is the stimulus for opening sodium channels suring an action potential?
depol
What is the threshold for stimulus (membrane potential starts at -90mV)?
-65mV
