Resting Membrane Potential

Question 1

A neuron’s membrane at rest

Answer 1

Resting membrane potential

Question 2

What is resting membrane potential determined by?

Answer 2

Non-gated channels (leak channels) (channels that are always open)

Question 3

Ion distribution in extracellular fluid

Answer 3

• Sodium (Na+)
• Chloride (Cl-)

Question 4

Ion distribution in intracellular fluid

Answer 4

• Potassium (K+)
• Organic anions

Question 5

What would happen if each ion was able to move in our out of the cell in the absence of others

Answer 5

Equilibrium potential

Question 6

Equilibrium potential of sodium (Na+)

Answer 6

• Would go in
• Polarize the membrane to +55mV

Question 7

Equilibrium potential of chloride (Cl-)

Answer 7

• Would go in
• Polarize the membrane to -60mV

Question 8

Equilibrium potential of potassium (K+)

Answer 8

• Would go out
• Polarize the membrane to -75mV

Question 9

What is resting membrane ion permeability determined by?

Answer 9

Number of non-gated ion channels present in the membrane

Question 10

The permeability of _____ is higher than _____ when the membrane is at rest

Answer 10

• Potassium
• Sodium

Question 11

The concentration gradient is maintained by the Na/K pump which sends:

Answer 11

• 3Na+ out
• 2K+ in

Question 12

___ is inside while ___ is outside

Answer 12

• K+
• Na+