[K+] on the inside of the cell compared with outside is:

• A. Higher on the outside, lower on the inside
• B. Higher on inside, lower on outside
• C. Equal on both sides
• D. Absent on the outside

Answer: (B)

Potassium concentration is much higher inside the cell than outside, and the cell actively maintains this gradient. TheNa+/K+ ATPase pumps 3 Na+ out for every 2 K+ in, using energy to keep intracellular K+ high. At rest, K+ leaks out through channels, but the pump constantly resupplies it, so the intracellular environment stays rich in K+ while the outside is comparatively low. This gradient is essential for the resting membrane potential and for K+ to move according to the electrochemical forces.

So the correct statement is that potassium is higher on the inside and lower on the outside.