Question: Calculate the amount of current (in nA) that flows during one AP for the [Na+] if the AP lasts for 1 msec.

Vm=-70 mV

Vo= 40

Initial [Na+]= 15 mM

axon is 10 cm long

radius is 10 um

epsilon= 8.85E-12 C^2/ N m^2

dialectric constant is 3

Question: The loss of water during a hot day causes the blood volume to decrease and the osmolality of bodily fluids to increase. Discuss how antidiuretic hormone can help to maintain homeostasis.