Electrochemical Signaling

Question 1

Pores:

Answer 1

always open and act like a tube through the membrane (Fastest)
Porins

Question 2

Channels:

Answer 2

Channels are gated, meaning they can be open or close depending on their confirmation, like tube with shutter
Na, K, Ca+ channels

Question 3

Carriers:

Answer 3

form a conduit that is never continuously open across the membrane. Like a tube with two shutters that aren’t open at the same time

Question 4

Nernst potential:

Answer 4

EMF = +- 61 log C1/C2
Veq = (RT/zF) ln([X out] / [X in])
Used to calculate the cell potential of an ion under non-standard conditions

High positive concentration on outside vs low positive concentration on inside = more positive equilibrium potential

Question 5

Action potential:

Answer 5

EPSPs and IPSPs are integrated at the cell bodies

Depolarization: sodium channels open, rush into cell. Eventually inactivate and close
Hyperpolarization: K+ channels open, membrane repolarizes. K+ rushes out of cell.
Membrane potential undershoots,

Question 6

Anesthetics:

Answer 6

Anesthetics have amino ester groups and mainly act as Na+ channel blockers
Originated with cocaine and now primarily use Procaine
When electrophysiological Na current is blocked, inhibition of pain increases