Membrane Potential

Question 1

Most cells have a negative resting membrane potential

Answer 1

True (usually between -30 and -50)

Question 2

Electrical gradient, think of one thing:

Answer 2

Opposites attract

Like charges repel

Question 3

Ionic Gradient consists of 2 things:

Answer 3

2 gradients:

Chemical and Electrical

Question 4

Vm

Answer 4

Membrane potential is difference in electrical potential between the INSIDE of the cell and the OUTSIDE

Question 5

Depolarization

Answer 5

Less polarizing (moving more towards 0)

Question 6

Ionic Equilibrium

Answer 6

Balance between chemical and charge

Question 7

Ionic gradient/equilibrium

Answer 7

A gradient resulting from combination of the electrical and concentration gradients acting on a specific ion. An ionic equilibrium occurs when the combined forces are balanced, although neither on its own may appear to be in balance

Question 8

To make an ionic gradient

Answer 8

Need:

Selective cell membrane

Na/K ATPase

Question 9

Permeability of the ions (by definition has charge)

Answer 9

Na+: Low at rest

Ca2+: low

K+: Higher at rest (100x that of Na+)

Cl-: moderate

Question 10

Amino acids (proteins) in the cell have a NEGATIVE charge OVERALL

Answer 10

True

Thus gives cell a negative charge inside and thus a negative membrane potential

Question 11

Na/K ATPase pump

Answer 11

3 Na+ OUT
2 K+ IN

Both are moving against their gradients