There are too many potassium ions inside a cell. As a result, the cell membrane expands and bursts. Which problem was the cell most likely haying?

Endosmosis of water into the cell leads to its bursting as the cell is not able to maintain its constant internal environment.

Explanation:

Increased potassium ion level in the cell makes its internal environment hypertonic with respect to its surroundings. Osmosis leads to entry of water into the cell to balance the increased potassium level. Due to excess of water that enters the cell, the cell volume increases leading to expansion and finally bursting of cell membrane.

"the cell was unable to maintain a stable internal environment" - APEX