When a nerve cell membrane is depolarized by 5 mV

A. True Depolarization opens sodium channels in the membrane.

B. True Positively charged sodium ions move down their electrochemical gradient making the inside of the fibre more positive.

C. True The fall in membrane potential increases the outward electrochemical gradient for the positively charged potassium ions; their exit tends to stabilize the mem-brane potential.

D. True The fall in membrane potential increases the inward electrochemical gradient for chloride; this again tends to restore the resting membrane potential.

E. False Not unless it reaches the threshold for firing.