Final answer:
When a cell wall is filled with water, the pressure inside the cell increases, reducing the inward diffusion of water. In plants, this influx of water produces turgor pressure, which supports the plant. However, if a plant is not watered adequately, the external fluid becomes hypertonic, causing water to leave the cell.
Step-by-step explanation:
When the inside of a cell wall is filled with water, several processes occur between the inside and outside of the environment. In organisms with cell walls, such as plants and fungi, the rigid wall allows water to flow into the cells and increase the pressure. This high pressure reduces the inward diffusion of water, eventually reaching a dynamic equilibrium. In plants, the influx of water produces turgor pressure, which stiffens the cell walls and supports the plant.
On the other hand, if a plant is not watered adequately or experiences drought, the external fluid becomes hypertonic, causing water to leave the cell. This condition, known as plasmolysis, leads to the loss of turgor pressure and wilting of the plant. Similarly, when a red blood cell is placed in a hypotonic solution, it will swell and burst, while a cell with a cell wall will swell but be prevented from further water entry by the tough wall.
Overall, the movement of water between the inside and outside of a cell wall depends on the solute concentrations and the nature of the external environment. The cell wall plays a crucial role in regulating the osmotic pressure and preventing cell lysis or excessive water loss.