Diffusion Potential , Resting Membrane Potential And Action Potential

Question 1

Define diffusion potential?

Answer 1

Is the potential difference generated across a membrane because of a concentration difference of an ion

Question 2

Define equilibrium potential ?

Answer 2

Equilibrium Potential Is the diffusion potential that exactly balances (opposes) the tendency for diffusion caused by a concentration difference.

Question 3

Solution A and B are separated by a semipermeable membrane that is permeable to K+ but not to C-, solution A is 100mM KCL and solution B is 1mM KCL , which of the following statements about solution A and solution B is true ?

Answer 3

k+ ions will diffuse from A to B until a membrane potential develop with A negative with respect to B

Question 4

Solution A and B are separated by a membrane that is permeable to Ca2+ and impermeable to Cl-. Solution A contains 10mM CaCl2, and solution B contains 1mM CaCl2, assuming that 2.3RT /F = Ca2+ will be at electrochemical equilibrium when ?.??

Answer 4

Solution A is -30mv

Solution B is + 30mv

Question 5

Depolarization?

Answer 5

Makes the membrane potential less Negative

Question 6

Hyperpolarization ?

Answer 6

Makes the membrane potential more negative

Question 7

What is inward current ?

Answer 7

It’s the flow of positive charge into the cell

Question 8

What’s outward current ?

Answer 8

It’s the flow of positive charge out of the cell

Question 9

Define Action Potential?

Answer 9

Action potential is the property of excitable cells that consists of a rapid depolarization, or upstroke, followed by repolarization of the membrane potential.

Question 10

Define threshold potential?

Answer 10

It’s when Depolarization proceeds slowly at first until it reaches a critical level , then an explosive depolarization takes place .