Question

the cell membrane-practice problems
48.00 points possible | due friday 10/24/25 at 11:59 pm
0/2 points eame
if you have ever had a stomach virus, you know how hard it can be to stay hydrated when everything you eat or drink seems to come right back up. if you become very dehydrated you may have needed to receive iv fluids to help keep your body functioning. your iv will typically contain saline (0.9% salt in sterile water) or another similar solution of sterile water and ions.
what would happen to your blood cells if you received an iv of pure water instead?
your cells would swell because the concentration of molecules in solution would now be higher inside the cell than outside the cell and water would diffuse through the membrane into your cells.
your cells would swell because the concentration of molecules in solution would now be higher outside the cell than inside the cell and water would diffuse through the membrane into your cells.
your cells would shrink because the concentration of molecules in solution would now be higher outside the cell than inside the cell and water would diffuse through the membrane out of your cells.
your cells would shrink because the concentration of ions would now be higher inside the cell than outside the cell and the ions would diffuse through the membrane out of your cells.

Explanation:

When considering the effect of an IV of pure water on blood cells, we look at osmosis. Osmosis is the movement of water across a semi - permeable membrane (in this case, the cell membrane) from an area of lower solute concentration to an area of higher solute concentration.
Blood cells have a certain concentration of solutes (molecules in solution) inside them. Pure water has a very low (virtually zero) concentration of solutes compared to the inside of the blood cell.
So, water will move into the cell (from the area of lower solute concentration - pure water outside the cell to the area of higher solute concentration - inside the cell) through the cell membrane.
As water enters the cell, the cell volume will increase, causing the cell to swell.

Answer:

Your cells would swell because the concentration of molecules in solution would now be higher inside the cell than outside the cell and water would diffuse through the membrane into your cells.