Does the cell membrane allow something to move out of the cell?

Yes, the cell membrane allows unwanted and toxic substances to move out of the cell. The cell membrane is selectively permeable. When the concentration of a substance such as water, oxygen, or carbon dioxide is higher inside the cell than it is outside the cell, the cell membrane allows it to move out of the cell. This helps the cell to maintain the correct concentrations of different substances so its internal environment remains balanced.