RESTING POTENTIAL IL/ PSW

Question 1

Fluid

Answer 1

components of cell membrane can move positions and move closer or farther away from each other

Question 2

degree of fluidity is affected

Answer 2

temp, chloestrol, saturated and unssaturated fatty acids

Question 3

mosaicism

Answer 3

cell membrane is made up of other components other than phospholipids such as chloestrol glycoproteins glycolipids

Question 4

what does ficks law describe

Answer 4

passive diffusion of molevules from an area of high concentration to low concentration passively down the concentration gradientgs

Question 5

Ji

Answer 5

flux of a ion

Question 6

Di

Answer 6

diffusion coefficent

Question 7

A

Answer 7

cross sectional area

Question 8

C1-C2- concentration difference

Question 9

X

Answer 9

distance over which diffusion takes place

Question 10

Jx=Px (Xo-X1)

Answer 10

Px = permeability coefficent Xo-Xi difference in the concentration of molecule x inside and outside the cell

Question 11

when concentration of molecule x is higher outside the cell (Xo) compared to inside (Xi) the flux is

Answer 11

positive

Question 12

when Xi is greater than Xo the flux is

Answer 12

negative

Question 13

non gated channels

Answer 13

leakage channels aka pores are conduits that are always open

Question 14

gated channels

Answer 14

pores that open and close in response to certain changes like voltage mechanical stretch chemical ligand binding etc

Question 15

tetramers 4 subunits

Answer 15

voltage gates Na+, Ca++ and K_ , Ca release channels

Question 16

Pentamers 5 subunits

Answer 16

nicotininc acetylcholine receptor channels triggered by binding molecules

Question 17

hexamers 6 subunits

Answer 17

half of a gap junction channel called a connexon made of 6 connecins

Question 18

Gap junction chanells are abundant in the heart ensuring fast and synchronized electrical signal to prevent ___

Answer 18

irregular heartbeats

Question 19

voltage gated channels

Answer 19

open and close due to changes in membrane potential

Question 20

ligand gated channels

Answer 20

open and close because of molecules binding to them

Question 21

a positive ion departing the cell created a positive current while a positive ion entering produces a

Answer 21

negative current

Question 22

how does resting membrane potential persist with ions continually leaking in and out

Answer 22

the Na+/K+ ATPase

Question 23

T or F
conductance is always positive

Answer 23

T

Question 24

nernst equation

Answer 24

The actual reduction potential of a half cell
will vary with the concentration of each chemical species in the cell. The relationship between the reduction potential E and the standard reduction potential E° is given by the following equation (also called the Nernst
equation)

Question 25

at steady state the net current is zero

Answer 25

INa + IK =0

Question 26

ion flux and direction are guided by the driving force

Answer 26

Vm-Eeq

Question 27

positive or negative current informs us about the ion flow direction

Answer 27

T

Question 28

cations a positive current denotes ___ flow while a negative current signfiies ___ flow and reverse for anions

Answer 28

outward inward

Question 29

ohms law

Answer 29

voltage = current * Resistance

Question 30

permeability is defined as a physical property of the membrane and is dependant on the _____

Answer 30

leak channels and ion channels

Question 31

what is inverse of resistance and is an electrical measure

Answer 31

Conductance

Question 32

T or false with 0 voltage the conductance will be 0 permeability however will not in cases where a voltage exists, conductance and permeability become the same thing

Answer 32

T

Question 33

in the situation where there are equal amounts of Na and K channels, the voltage 0 as the ____ potential of ___ and ___

Answer 33

electric potential of Na and K cancel each other out.