Final answer:
In a hypotonic solution, water will enter a cell with a higher internal solute concentration, potentially causing it to swell and burst. Cells like red blood cells lack regulatory mechanisms for water control and can undergo hemolysis in these conditions.
Step-by-step explanation:
When a cell that is 75% water is placed into a solution that is 100% water, the solution outside the cell is hypotonic. Due to osmosis, where water moves from a lower concentration of solutes to a higher one, water will rush into the cell. Given that the cell membrane has a fixed surface area, and most cells have mechanisms to prevent them from taking on too much water, most will manage this condition to some extent. However, cells such as red blood cells lack these controls and can undergo hemolysis, where they swell up with water and eventually burst because they cannot regulate the inflow of water.