Neurophysiology (Test 2)

action potential is a _____ event

membrane

transport of materials in the neuron is a _____ event

axonal

microfillament diameter

6-7 nm

microtubules diameter

25 nm

intermediate filaments diameter

8-12 nm

which microtubule associated (MAP) protein transports substances in an anterograde manner?

kinesin

which microtubule associated protein (MAP) transports substances in an retrograde manner?

dynein

what rate is fast transport in a neuron

2-40 cm/day

which parts of the neuron are transported in a retrograde manner?

synaptic vesicles, axoplasmic substances, some viruses and toxins

what rate is slow transport in a neuron

.2-4mm/day

which type of transport is responsible for repairing/regenerating tips of damaged axons?

slow

what are the two properties of neurons

irritability, conductivity

true/false: unmyelinated axons allow for faster conduction velocity

false

what dictates the electrical activity of a membrane

ion fluxes

what are the three major things to be considered in neurophysiology

membrane potential, intracellular transport, ion fluxes

which has a higher ECF concentration, Na or K?

Na

which has a higher ICF concentration, Na or K?

K

on which side of the cell membrane is Cl concentration the highest?

ECF

which membrane potential is the threshold for an action potential

-55mV

what are the two types of graded non-propagating post-synaptic potentials?

excitatory and inhibitory

true/false: IPSP and EPSPs always result in an action potential

false (must be graded to threshold)

what ion rushes in to the cell following a threshold stimulus and where does it rush in to?

Na, initial segment

which ion rushes out of the cell during repolarization?

K

action potentials will continue to fire multiple times across a neuron until what happens

acetylcholine esterase removes ACH from the receptor causing EPSPs

in what period can no impulse be fired along a neuron

absolute refractory period

in which period could an impulse still be fired if the stimulation was great enough?

relative refractory period

about how fast is an action potential

3 milliseconds

about which charge is the overshoot part of the action potential

40 mV

definition of internal and external mesaxon

where the myelin sheath starts and stops wrapping around

what is 1

generator (graded) potential

what is 2

threshold

what is 3

depolarization

what is 4

overshoot

what is 5

repolarization

what is 6

hyperpolarization

which one is the absolute refractory period (pink/blue)

pink

which one is the relative refractory period (pink/blue)

blue