Question

Let's consider a scenario in which the resting membrane potential changes from −70 mv to +70 mv, but the concentrations of all ions in the intracellular and extracellular fluids are unchanged. predict how this change in membrane potential affects the movement of na+. the electrical gradient for na+ would tend to move na+ __________ while the chemical gradient for na+ would tend to move na+ __________. view available hint(s)

Answer 1

Let's consider a scenario in which the resting membrane potential changes from −70 mV to +70 mV, but the concentrations of all ions in the intracellular and extracellular fluids are unchanged. Predict how this change in membrane potential affects the movement of Na+. The electrical gradient for Na+ would tend to move Na+ Outside the cell (extracellular) while the chemical gradient for Na+ would tend to move Na+ Inside the cell (intracellular).

The electrical gradient is defined as the + goes to the - and the - goes to the +
Na + has a positive charge, but there's more positive charge inside the cell than outside (due to potassium), therefore, Na+ goes extracellular (out)
The concentration gradient considers that the ion will go from the most concentrated to at least concentrated by passive diffusion so no trans-membrane proteins in the game attention.Na + is very concentrated in extracellular and few intracellular, therefore, it tends to go intracellular (in).