W9 Electrochemical signaling

Question 1

osmolality

Answer 1

the total [ ] of all particles free in solution

Question 2

simple diffusion and facilitated diffusion trend for rate of diffusion vs [ ] of substance

Answer 2

simple - straight line
facilitated - log of x (has a cap)

Question 3

Na+/K+ how many each, what direction, [ ] high for what

Answer 3

3 Na+ out
2 K+ in

The sodium and chloride ion concentrations are lower inside the cell than outside, and the potassium concentration is greater inside the cell

Question 4

calcium higher or lower in cell

Answer 4

higher ca on outside, lower ca on inside

Question 5

pores vs channels vs carriers

Answer 5

pores - always open
PhoEporin, Aquaporin
channel - gated (open and close depending on conformation)
ex:Na, K, Ca2+ channels
carriers - never continuously open (tube 2 shutters that aren’t open at the same time)
ex: SLCs GLUT1

Question 6

voltage gated channel, each subunit has how many segments what shape

Answer 6

6 helical segments

Question 7

Nicotinic Ach receptor channel how many subunits

Answer 7

pentamer

Question 8

Voltage-gated Na+, Ca2+, K+, Ca-release channel how many subuntis

Answer 8

tetramer

Question 9

hemijunction, or connexon, how many subunits

Answer 9

hexamer

Question 10

what is the only primary active transport mechanism for Na+

Answer 10

Na+/K+ pump/ATPase

Question 11

what are the subunits for Na+/K+ pump/ATPase

Answer 11

10 alpha subunits (10 transmembrane domains)
1 beta subunit (1 transmembrane region)

Question 12

primary vs secondary active transport

Answer 12

secondary couples w movement of another solute

Question 13

Nernst potential (eq potential) formula

Answer 13

V[eq] = RT/zFln(out/in)

Question 14

excited postsynaptic potential / inhibitory postsynaptic potential are integrated at where

Answer 14

cell bodies

Question 15

how does the anesthetic Procaine (Novocain or novocaine) work

Answer 15

acts as a Na+ channel blocker
has amino ester group