Membrane Potential

Question 1

What is a nerve impulse?

Answer 1

An electrochemical charge which travels along a nerve fibre. May be continuous (unmyelinated fibre) or via saltatory conduction (myelinated fibre)

Question 2

What creates membrane potential?

Answer 2

Difference in ion concentration across the cell membrane / Differences in distribution of Na and K on either side of the cell membrane.

Question 3

What is the resting membrane potential (mV)?

Answer 3

-70mV

Question 4

Sodium concentration is how many times greater outside the cell that within?

Answer 4

10x

Question 5

Potassium concentration is how many times greater inside the cell than outside?

Answer 5

30x

Question 6

What membrane protein controls the permeability of the membane?

Answer 6

Sodium potassium pump