General Biology Laboratory 101: What is the reasons for why the volume of the cell in hypertonic solution has reduced, and why it increased in the hypotonic solution?

The volume of a cell in a hypertonic solution is reduced due to the process of osmosis. Osmosis is the movement of water across a selectively permeable membrane from an area of high water concentration (low solute concentration) to an area of low water concentration (high solute concentration). In a hypertonic solution, the concentration of solutes outside the cell is higher than that inside the cell. As a result, water flows out of the cell to balance the solute concentrations on both sides of the cell membrane. This outward flow of water causes the cell to shrink and its volume to decrease.

Conversely, when a cell is placed in a hypotonic solution, the situation is the opposite. The solute concentration outside of the cell is lower than that inside the cell. This causes water to move into the cell by osmosis, as water follows the gradient from high to low concentration of solute. As water enters the cell, it causes the cell to swell and potentially burst if the incoming water is not managed through other cellular mechanisms. This inflow of water leads to an increase in the volume of the cell.