* Turgor Pressure: Cells gain stiffness primarily due to turgor pressure. This pressure is created when water enters the cell and pushes against the cell wall, making it rigid.
* Hypotonic Solutions: When a cell is in a hypotonic solution, meaning the solution has a lower concentration of solutes than the cell's cytoplasm, water moves into the cell by osmosis. This leads to increased turgor pressure and a more rigid cell.
So, a stiffness cell with plenty of water is essentially a cell with high turgor pressure.
Important Note: The term "stiffness cell" isn't commonly used in biology. We usually refer to cells with high turgor pressure as being turgid or firm.