Exam 1 properties of excitable membranes

Question 1

ions lining intracellular side of membrane

Answer 1

anions

Question 2

ions lining extracellular side of membrane

Answer 2

cations

Question 3

resting membrane potential of excitable cells

Answer 3

-70 mV, set by potassium leak channels

Question 4

conductance refers to?

Answer 4

ion permeability via an open gate

Question 5

resistance refers to?

Answer 5

ability of ions to pass membrane
high resistance: closed channel
low resistance: open channel

Question 6

equilibrium potential

Answer 6

membrane potential when chemical force and electrical force are opposite and equal, so no net ion movement

Question 7

inward current

Answer 7

cell depolarization
cations in, anions out

Question 8

outward current

Answer 8

hyper polarize or repolarize cell
cations out or anions in

Question 9

L-type calcium channels

Answer 9

allows calcium entry when depolarization reaches synaptic terminal or during muscle contraction

Question 10

hyperkalemia effects

Answer 10

depolarize cell so lower RMP, less likely to have action potentials/ less excitable
muscle weakness